CN104246916A - Cns-shielded wires - Google Patents

Abstract

A shielded wire includes a carbon nanostructure (CNS)-shielding layer including a CNS material in a matrix material, the CNS-shielding layer being monolithic and disposed about a dielectric layer and a conducting wire, wherein the dielectric layer is disposed between the CNS-shielding layer and the conducting wire. An extruded thermoplastic jacket includes a CNS material, the extruded thermoplastic jacket being configured to protect at least one wire. A thermoplastic article includes a CNS-infused fiber material and a flexible thermoplastic.

Description

CNS shielding conductor

the statement of related application

The application is the U. S. application 12/766 submitted on April 23rd, 2010, the cip application of 812, described U. S. application requires again the U.S. Provisional Application 61/172 that on April 24th, 2009 submits to, the U.S. Provisional Application 61/173 that on April 28th, 503 and 2009 submits to, the rights and interests of 435, the full content of described two U.S. Provisional Applications is all by reference to being incorporated herein.

Technical field

The present invention relates generally to the material absorbing electromagnetism (EM) radiation.

Background technology

The undesired interference that the electromagnetic conductive sent by external source or electromagnetic radiation cause adversely can affect the performance of Electrical and Electronic circuit.These undesired interference interruptible price, obstruction or otherwise reduce the effective performance of Electrical and Electronic circuit.Shielded electrical and electronic circuit are developed by housing (housing) structure of external electromagnetic interference (EMI).Usually EMI shielding is realized by shell structure being configured to restriction penetration by electromagnetic fields to internal closed space.Use the shell structure of conductive material manufacture to be called " Faraday cage " (Faraday cage), it is used as the barrier of block electromagnetic field.More specifically, and as known in the art, Faraday cage is the shell (enclosure) that formed by electric conducting material and can in order to stop external electromagnetic interference.When described shell structure is subject to external electromagnetic power, generation current in conductibility shell structure, described electric current creates antagonism again and cancels the electromagnetic force of external electromagnetic field.

Similarly, lightning-protection system utilizes conductibility housing to provide the low impedance path of lightning current, reduces the thermal effect flowing through the electric current of conductibility shell structure simultaneously.These thermal effects reduced reduce by the fire hazard caused of being struck by lightning.

Usually, for the manufacture of this type shielding EMI shell structure and/or for lightning protection application conductive material comprise high conductance metal, such as copper and aluminium.But, these Metal Phase counterweights.Lighter material such as composite material (composite) or those " composite materials " of being even made up of Conductive fiber such as carbon normally insulating properties, and therefore there is owing to there is host material (such as resin) poor EMI shielding and lightning protection characteristic.Composite material although it is so caters to the need because of its particular characteristics, but is not suitable for the application of the good EMI shielding of needs and/or lightning protection characteristic.

In order to improve EMI shielding and the lightning protection characteristic of composite material, metallic stuffing, metal coating, wire netting or other metal component are introduced in composite material.But these introducings can produce heavier and more complicated composite material.Expect to have the optional composite material being applicable to EMI shielding and/or lightning protection application.Present invention accomplishes this needs and provide associated benefits.

Summary of the invention

In some respects, execution mode disclosed herein relates to for the composite material in electromagnetic interference (EMI) shielding application, it comprise be arranged at host material at least partially in the fiber material that injects of carbon nano-tube (CNT).Described composite material can absorb electromagnetism (EM) radiation, reflection EM radiation or its combination in the frequency range of about 0.01MHz to about 18GHz.With measured by electromagnetic interference (EMI) screening effectiveness (shielding effectiveness, SE), the EM screening ability of described composite material is in about 40 decibels (dB) scope to about 130dB.

In some respects, execution mode disclosed herein relates to a kind of method manufacturing above-mentioned composite material, described method is included in a part for host material the fiber material arranging CNT and inject, wherein control the orientation of fiber material in host material that described CNT injects, and this host material of solidification.The controlled tropism control of the fiber material that described CNT injects injects the relative orientation of CNT thereon in overall composite construction.

In some respects, execution mode disclosed herein relates to the panel comprising above-mentioned composite material.Described panel is suitable for and shields the means for engaging in applying (interface) for EMI.Described panel is also equipped with electrical ground (electrical ground).

In some respects, execution mode disclosed herein provides one to comprise the shielding conductor of carbon nano-structured (CNS) screen, described CNS screen comprises CNS material in host material, described CNS screen is (monolithic) of monolithic and is arranged on around wire and optional dielectric layer, with when dielectric layer exists, this dielectric layer is arranged between described CNS screen and described wire.

In some respects, execution mode disclosed herein provides a kind of extrusion type thermoplastic sheath comprising CNS material, and described extrusion type thermoplastic sheath is configured to protection at least one line.

In some respects, execution mode disclosed herein provides a kind of thermoplastic article, it comprises fiber material and the flexible thermoplastic resin of CNS injection, described flexible thermoplastic resin comprises at least one be selected from PETG ester (PET, Mylar), polytetrafluoroethylene (PTFE) and polyvinyl chloride (PVC).

Accompanying drawing explanation

Fig. 1 shows transmission electron microscope (TEM) image by the many wall CNT (MWNT) of continuous CVD technique growth on AS4 carbon fiber.

Fig. 2 shows the TEM image by the double-walled CNT (DWNT) of continuous CVD technique growth on AS4 carbon fiber.

Fig. 3 shows scanning electron microscopy (SEM) image of the CNT of growth from protective coating (barrier coating), wherein the nano-particle catalyst forming CNT is mechanically injected carbon fibre material surface.

Fig. 4 shows SEM image, and it is presented at the consistency of distribution of lengths in 20% of the target length of about 40 microns of the CNT that carbon fibre material grows.

Fig. 5 shows display protective coating to the SEM image of the impact of CNT growth.When applying protective coating, the well-arranged CNT that growth is fine and close, and when there is not protective coating, do not grow CNT.

Fig. 6 shows the low magnification ratio SEM of the CNT on carbon fiber, which show the uniformity of the CNT density on whole fiber in about 10%.

Fig. 7 shows the cross section of the EMI shielding composite with the fiber material that carbon nano-tube (CNT) is injected.

Fig. 8 shows the fibre bundle of the carbon nano-tube injection being suitable for use as EMI shielding material in coating on goods, and these goods are such as EMI shielding panels.

Fig. 9 shows applying on the composite with the fibre bundle coating that the carbon nano-tube improving the EM shielding characteristic of composite material is injected.

Figure 10 shows the schematic diagram of the coating system of the fiber that carbon nano-tube is injected.

Figure 11 shows the method for the carbon fibre material that the CNT for the manufacture of exemplary embodiment of the invention injects.

How Figure 12 can inject carbon fibre material in a continuous process to reach thermal conductivity and conductivity improvement by CNT if showing, comprise the object of EMI shielding.

Figure 13 show how can in a continuous process by CNT implantation glass fiber material to reach thermal conductivity and conductivity is improved, comprise the object of EMI shielding.

Figure 14 shows the EMI screening effectiveness of the fiberglass-epoxy composite material that CNT injects.

Figure 15 shows the EMI screening effectiveness of the carbon fiber epoxy resin composite material that CNT injects.

The figure that the average EMI screening effectiveness that Figure 16 shows the composite material that CNT injects changes with composite material CNT % by weight.

The figure that the composite material that Figure 17 shows CNT injection changes with composite material CNT % by weight at the average EMI screening effectiveness of low-frequency band.

The figure that the composite material that Figure 18 shows CNT injection changes with composite material CNT % by weight at the average EMI screening effectiveness of high frequency band.

Figure 19 shows the figure with the wire shielded according to the CNS screen of execution mode disclosed herein.

Figure 20 shows the typical coaxial cable 2000 with paper tinsel 2010, and the available CNS screen according to execution mode disclosed herein replaces described paper tinsel 2010.

Figure 21 shows the typical wire harness 2100 with paper tinsel 2110, and the available CNS screen according to execution mode disclosed herein replaces described paper tinsel 2110.

Figure 22 shows the typical wire harness 2200 with paper tinsel 2210, and the available CNS screen according to execution mode disclosed herein replaces described paper tinsel 2210.

detailed Description Of The Invention

The present invention partly relates to the composite material providing EMI to shield.The composite material of shielding EMI disclosed herein has the fiber material that the carbon nano-tube (CNT) be arranged in a part for host material is injected.CNT has the electromagnetic absorption character of expectation because its aspect ratio is high.CNT in composite material of the present invention can absorb the EM radiation frequency of wide region, and the energy such as absorbed to dissipating electrical ground and/or the energy absorbed that dissipates in the form of heat.Mechanically, CNT also can reflect EM radiation.In addition, for EMI shielding application, any combination absorbing and reflect is all applicable, as long as the transmissivity of electromagnetic radiation minimized.No matter actual exercisable mechanism, and without being bound by theory, composite material of the present invention is by reducing and/or preventing a large amount of electromagnetic interference and operate.

The composite material of shielding EMI of the present invention can improve for the shielding character of the material in EMI shielding application.In some embodiments, the EMI shielding of the improvement of dielectric and conductive composite given by the fiber that described CNT injects, thus produces the ability using low weight, high strength composite.Some these type of composite materials previously may be applied limited because its EMI screening ability is poor inherently.

The composite material of shielding EMI of the present invention can provide sorbent surface, described sorbent surface is almost the black matrix (black body) of the following different piece containing electromagnetic spectrum, and it comprises the visible ray of various radar, infrared ray (IR) and other parts.In order to realize black matrix class feature, the CNT density on fiber material can be controlled.Therefore, such as, the refractive index of the fiber material of adjustable CNT injection is with the refractive index of close match air.According to fresnel's law (Fresnel's law), this is the situation when minimize reflections.Although minimum reflected is applicable to optimize EM absorption, can be also minimize the transmissivity through EMI screen by composite Materials Design of the present invention.In other words, to providing the EMI degree shielded, absorption is applicable.For not being the specific wavelength that effectively absorbs of fiber material that CNT injects, reflection being provided or providing the secondary structure (secondary structure) that can absorb the radiation do not absorbed for the fiber material of CNT injection to be favourable.With regard to this, the progressive stratification of the fiber material that different CNT injects can be advantageously provided to provide optional absorption characteristic.Alternatively, or except multilayer material, introduce reflecting material and also can use, this reflecting material also can be the fiber material that CNT injects.Therefore, such as, composite material of the present invention can have the multiple absorption and/or the reflector that comprise the fiber material that CNT injects.

Described fiber material itself is organize CNT to become the support (scaffold) of array, and described array provides enough CNT density to produce effective permeation pathways (percolation pathway) with the dissipation energy when EM radiation absorption to whole composite material.The CNT of injection can be adjusted to and there is even length, density, and the controlled orientation on fiber material and in whole composite material, to maximize EM radiation absorption.

By depending on CNT to obtain EM shield property, described composite material can utilize the fiber material and/or matrix with conductibility or insulating properties.In addition, the composite material of described shielding EMI can be integrated into a part for the surface texture of the goods wherein using this composite material.In some embodiments, whole goods can be used as EMI screen, but not only surperficial.In some embodiments, the fiber material that CNT injects can be used as the coating of the prefabricated composite material of EMI shielding application.

Hereafter further describe the manufacture method producing the fiber injected for the CNT of the material of above-mentioned shielding EM.Described method can be suitable for extensive Continuous maching.In the process, CNT be grown directly upon carbon, glass, pottery maybe can be wound around on like fibrous the material such as tow or rove of dimension.The character of CNT growth makes, deposition certain length fine and close covering (forest), can long at about 5 microns to about 500 microns between regulate described length, control this length by many factors as described below.Can make this covering orientation as follows, this orientation makes CNT perpendicular to the surface of each independent long filament of fiber material, thus provides radial covering.In some embodiments, CNT can be processed further to provide the orientation of the axle being parallel to fiber material.The fiber material that gained CNT can be injected is wound around as when manufacturing, maybe can be weaved into fabric for the composite material manufacturing the shielding EMI used in EMI shielding application.

As used herein, term " shielding EMI sends out composite material " refers to following any composite material, it at least has the fiber material that the CNT be arranged in host material injects, and it can realize any combination of absorption or reflecting electromagnetic radiation, minimizes transmissivity simultaneously.The composite material of shielding EMI of the present invention has at least three kinds of components, i.e. CNT, fiber material and host material.These components produce organized level, wherein organize described CNT by the fiber material being injected into CNT.The fiber material organizing described CNT to inject by the host material wherein arranging CNT injection fiber material again.This is formed with the composite material utilizing bulk carbon nanotube usually to be prepared by following technology and contrasts: various blended, mix, extrude and/or pultrusion technique.The present invention shields the CNT Absorbable rod of the composite material of EMI or reflects the electromagnetic radiation relevant to transmission source.Any absorbed electromagnetic radiation all can change into such as the signal of telecommunication, guide to electrical ground and/or change into heat.

As used herein, term " electromagnetic radiation " or " EM radiation " refer to any EM frequency in about 0.01 megahertz to about 300 gigahertz range.Such as in low frequency (LF to UHF) and high frequency (L is to K-band) radar, the composite material of shielding EMI of the present invention is especially effective, as described further below.

As used herein, term " electromagnetic interference " or " EMI " refer to that electronic installation outage occurs when near the electromagnetic field of originating from another (EM field)." EMI shielding " adopts the method that can prevent the material of this interference.These materials can absorb and/or reflection interference electromagnetic radiation." EMI screening effectiveness " or " EMI-SE ", " screening effectiveness " or " SE " or its grammer equivalent refer to that material weakens/protect electronic installation with the normalization measurement of the ability of the interference of the EM field of originating from another.EMI-SE is measured as before shielding interference electromagnetic signal strength and the function of difference of its intensity after shielding, and usually measures with decibel (dB) under the characteristic frequency measured with hertz (Hz) such as megahertz (MHz), gigahertz (GHz) etc.

As used herein, term " EM screening ability " refers to that composite material of the present invention absorbs or reflect the ability of the electromagnetic radiation of any frequency.It is measured by standardization EMI-SE measurement.

As used herein, term " fiber material " refers to have any material of fiber as its basic structure component.Fiber, long filament, yarn, tow, tow, tape (tape), fabric and nonwoven fabrics, folded yarn (ply), mat, 3D fabric construction etc. contained in this term.Described fiber material can be any organic or inorganic material, comprises carbon, glass, pottery, metal, and organic fiber such as aromatic polyamides, or natural organic fiber such as silk, cellulose fibre etc.

As used herein, term " can be wound around dimension " and refer to that the length of at least one dimension of fiber material is not limit, thus allows described material to leave on bobbin or mandrel.The fiber material that " can be wound around dimension " has at least one following dimension, and its instruction will be processed in batches or continuously and is used for CNS as described herein and inject.The fiber material that " can be wound around dimension " can be used as glass, carbon, pottery and similar products and commercially available.The example of the exemplary carbon fibre material of the be wound around dimension of commercially available acquisition is: Tekes (tex) value is 800 (1 Tekes=1g/1, AS412k carbon fibre tow (the lattice Raphael company (Grafil of Sacramento, California of 000m) or 620 yards/pound, Inc., Sacramento, CA)).Can obtain the business carbon fibre tow of such as 5,10,20,50 and 100 pounds (for having high weight, the bobbin of usual 3k/12K tow) bobbins especially, but larger bobbin may need special order.Method of the present invention easily operates with the bobbin of 5 to 20 pounds, but also can with larger bobbin.In addition, can preparatory machining operations be introduced, its by very large such as 100 pounds or larger can be divided into easy-to-handle size by coiling length, such as two 50lb bobbins.

As used herein, term " carbon nano-tube " (CNT, plural number CNTs) refer in a large amount of cylindrical carbon allotropes of fullerene family any one, comprise Single Walled Carbon Nanotube (SWNT), double-walled carbon nano-tube (DWNT) and multi-walled carbon nano-tubes (MWNT).CNT or can be open by fullerene shape building blocks.CNT comprise encapsulation other material those.The disclosed herein CNT being injected into various fibrous substrate occurs with the form with the array of complicated form, and described complicated form can comprise independent CNT, altogether wall CNT, branch CNT, the crosslinked CNT etc. of random distribution.Generally speaking, complicated CNT form is called " carbon nano-structured " or " CNS " (plural CNSs) herein.Due to this complicated form, therefore CNS is different from the array of independent CNT.

As used herein, " uniform length " refers to the length of the CNT grown in the reactor." even length " refer to between about 1 micron to about 500 microns change CNT length, described CNT have tolerance be add or deduct total CNT length about 20% or less length.Under very short length such as 1-4 micron thickness, this error may about add or deduct 20% to about adding or deduct 1 micron in total CNT length, namely just over total CNT length about 20% scope in.When being applied to EMI shielding, the length (and coverage density) of described CNT can be used for regulating EM radiation absorption and/or reflection and can be optimized for the absorption maximum in target EM frequency range or reflection.

As used herein, " be evenly distributed " density CONSENSUS of the CNT referred on carbon fibre material." be evenly distributed " and refer to that the tolerance of the density of described CNT on carbon fibre material is for adding or deduct about 10% coverage rate, described coverage rate is defined as the percentage of the surface area of the fiber covered by CNT.For the 5 wall CNT of diameter 8nm, this is equivalent to ± 1500 CNT/ μm ².Space in this numerical value hypothesis CNT can be filled.

As used herein, term " CNT % by weight " refers to weight or the mass percent of the CNT existed in final composite material.This percentage represents that the total weight of CNT in composite material is multiplied by the ratio of 100% divided by the total weight of final composite construction." CNT % by weight " is for combining the material character of CNT distribution and CNT length.Therefore, by " CNT % by weight " for describing in composite material CNT to the impact of average EMI SE.Such as, as shown in Figure 16, for the average EMI SE of 0-60dB, adopt the CNT % by weight of <1%, for the average EMI SE of 60-80dB, adopt CNT % by weight between 0.5-2%, and for the average EMI SE of >80dB, adopt the CNT % by weight of >2%.

As used herein, term " injection " (infused) refers to combination, and " injection " (infusion) refer to the process of combination.This combination can relate to the physical absorption of direct covalent bond, ions binding, π-π and/or Van der Waals force mediation.Such as, in some embodiments, described CNT directly can be incorporated into carbon fibre material.In conjunction with can be indirectly, CNT is injected carbon fibre material by such as, transition metal nanoparticles by being arranged on protective coating between CNT and carbon fibre material and/or intervention.The carbon fibre material that CNT disclosed in this article injects, can by " injection " carbon fibre material directly or indirectly described above for carbon nano-tube.Wherein the concrete mode of CNT " injection " carbon fibre material is called as " binding pattern " (bonding motif).

As used herein, term " transition metal " refers to any element in periodic table d district or mischmetal.Term " transition metal " also comprises salt form such as oxide, carbide, the nitride etc. of (base) transition metal substantially.

As used herein, term " nano particle " or NP (plural NPs) or its grammer equivalent refer to the particle of the size of equivalent spherical diameter between about 0.1 to about 100 nanometer, but NP is without the need to for spherical.Transition metal NP serves as the catalyst of the CNT growth on carbon fibre material especially.

As used herein; term " sizing agent (sizing agent) ", " fiber sizing agent " or only " starching " all refer to; the material used in carbon and glass fibre (maybe may need other fiber any of protective finish) manufacture as coating to protect the integrality of fiber; the interfacial interaction of the enhancing between fiber and host material is provided in the composite, and/or the specific physical property of change and/or reinforcing fiber.In some embodiments, the CNT being injected into fiber material is equivalent to sized fiber.That is, described CNT provides protection to a certain degree to fiber, and therefore CNT is equivalent to sizing agent.

As used herein, term " host material " refers to following body phase material (bulk material), and it can be used for, with specific orientation, comprising random orientation, organizes the carbon fibre material that the CNT of starching injects.By giving the physics of fiber material and/or some aspects of chemical property of CNT injection to host material, host material can benefit from the existence of the fiber material that CNT injects.In EMI shielding application, host material is combined with fiber material, provides better CNT density and CNT tropism control than by only simple mixed C NT and matrix available CNT density and CNT tropism control.The density of the fiber material that CNT injects and " filling " (packing) can provide permeation pathways, and it is by providing more effectively dissipation institute's absorption of electromagnetic radiation or providing the means of usable reflection and improve EMI screening effectiveness.

As used herein, term " the material time of staying " refers to that the discrete point along the fiber material that can be wound around dimension is exposed to the time span of CNT growth condition in this article in described CNT injection technology process.This definition comprises the time of staying when adopting multiple CNT growth room.

As used herein, term " linear velocity " refers to the speed fiber material charging that can be wound around dimension can being passed through described CNS injection technology herein, and its centerline velocities is the speed by one or more CNS rooms length being determined divided by the material time of staying.

In some embodiments, the invention provides a kind of composite material shielding EMI, its comprise be arranged on host material at least partially in (CNT) fiber material of injecting.Described composite material can absorb or be reflected in the EM radiation in about 0.01MHz to about 18GHz frequency range.EMI screening ability can be measured as electromagnetic interference (EMI) screening effectiveness (SE), and it can in about 40 decibels (dB) scope to about 130dB.Such as, in fig. 17, for HF, VHF and UHF waveband, improve CNT % by weight can by EMI SE from be low to moderate 40dB be increased in the composite nearly 20%CNT % by weight up to 70dB.EMI SE according to Figure 17, LF wave band usually can not be subject to the appreciable impact of raising CNT % by weight and keep constant at about 75dB.About Figure 18, as one man provide about 60dB EMI SE CNT existence under, L-band EMI SE also relative constancy.S and C-band have almost identical reaction because EMI SE can from the 70dB under 1 % by weight CNT under 20 % by weight CNT up in the scope of 90dB.Finally, the EMI SE of X and K-band illustrates similar reaction, and the CNT being wherein low to moderate 1 % by weight produces the EMI SE of 60dB, and produces EMI SE between 120 and 130dB up to the CNT of 20 % by weight.These shielding materials only have exemplary.One of skill in the art will recognize that the fiber material that such as multi-layer C NT can be used to inject is to realize further screening effectiveness, and CNT density, length and orientation can be changed with by changing the absorption of fiber material that CNT injects or the combination of reflectivity properties regulates screening effectiveness.

Those of ordinary skill in the art also will recognize that SE becomes with EM radiation frequency.Therefore, the SE under 2GHz can be different from the SE under 18GHz.Those of ordinary skill in the art are also shielding recognizing in relevant application with EMI, expect to absorb EM radiation or reflection EM radiation.By contrast, such as in stealth application in the radar absorption of signal controlling, expect to manufacture the material absorbing and/or send EM radiation.From mechanics viewpoint, any absorption characteristic provided by the fiber material that there is CNT injection is both benefited from EMI shielding and radar absorption application.Transmissivity or the reflectivity of non-radiation-absorbing such as can be measured by the intrinsic property of other parameter such as body phase matrix.In some embodiments, on fiber material, maximized CNT load (loading) can provide the composite material of performance as reflective metal, and it is specially adapted to EMI shielding application.

The composite material of described shielding EMI comprises the fiber material of following CNT injection, and its usual fiber material such as tow, rove, fabrics etc. by CNT being injected " continuously " or " can be wound around " length are upper and construct.SE and therefore EM radiation absorbing capacity can be depending on such as CNT length, CNT density and CNT orientation and become.The method manufacturing the fiber material that CNT injects allows the composite material of the shielding EMI be constructed as follows, and it has the absorption and/or albedo that fully limit.The CNT length on fiber material and orientation is controlled in CNT growth method hereinafter described.Providing usually at the CNT of fiber axis product growth in the CNT orientation of fiber peripheral from this growing method.By machinery or chemical means or by using electric field to realize being injected into reorientation after the growth of the CNT of fiber.In some this execution modes, described CNT can reorientation to lay along fiber axis.In described composite material, the relative orientation of CNT is controlled by method for composite material again, and described manufacture method determines the direction of the fiber that CNT injects.

The composite material structure of shielding EMI of the present invention can be become absorb and/or reflect one or more EM radiating bands.In some embodiments, can provide single can the fiber that injects of the CNT of coiling length, it different piece of coiling length can have different CNT length and CNT orientation, to maximize absorption and/or the reflection of different EM radiating bands along single.Alternatively, can arrange in the composite have different CNT length and/or orientation multiple can the fiber material of coiling length to reach identical effect.Arbitrary strategy all provides different EM radiation absorption and/or reflection characteristic to the layer in composite material.Multiple orientations of CNT also allow the composite material shielding EMI to absorb and/or reflection impacts electromagnetic radiation on the composite from multiple EM radiation source with different incidence angles.

Persons of ordinary skill in the art will recognize that arbitrary specific part of the fiber material that CNT injects all can show EM and absorb and reflectivity properties, be also even like this under the single wavelength of EM radiation.Therefore, the EM screening effectiveness of fiber material that given CNT injects represent its absorb and reflection EM radiation combination ability and it is without the need to being only absorbing material or reflecting material.When multi-ply construction, different layers can be designed to mainly reflect, and other layer can be designed to mainly absorb.

CNT filling in composite construction can provide permeation pathways with the energy of the EM radiation of any absorption of dissipating.Without being bound by theory, this can be produced by CNT and CNT point cantact routine as in figures 7-9 or staggered engage (interdigitation) of CNT and CNT.In some embodiments, the EM power conversion of absorption any in CNT can be become the signal of telecommunication, the described signal of telecommunication can with Computer systems to regulate the orientation of the goods such as panel introducing the composite material shielding EMI, such as to maximize EM radiation absorption in response to EM radiation transmission source or the EM signal that reflects detecting in application.Similarly, the ability reflecting EM radiation also can be dependent on CNT density and orientation.Such as, comprising under the high CNT density being greater than about 1%, described CNT partly can be equivalent to the metal reflecting EM radiation.

In some embodiments, provide the composite material of shielding EMI as the part for the whole goods in stealth application or structure.In such execution mode, by being mainly the mechanism of absorption, simultaneously minimum reflected mechanism and the feature of shielding EMI is provided.In some such embodiments, the density of the CNT on the fiber material that adjustable CNT injects, maximizes the material of EM radiation absorption close to air refraction with minimum reflectance to provide refractive index.

The fiber material that the CNT of shielding EMI injects can be provided in a part for whole composite construction.Such as, composite construction can have the fiber material of introducing CNT injection to absorb and/or to reflect the surface " skin " of EM radiation.In other embodiments, the composite material of EMI can be applied to shield as the coating on the existing surface of another composite material or other goods.In some embodiments, coating adopts overcut fibre material, and it contributes to preventing, and conventional coating is contingent peels off.In addition, when applied as a coating, finishing coat (overcoating) the described composite material shielding EMI of protection further can be used.In addition when applied as a coating, the matrix of the fibrous composite of CNT injection can close match integrally-built body phase matrix or identical with it to be provided in combination excellent between coating and structure.

The fiber material providing the CNT of the composite material of shielding EMI to inject, wherein injects the part uniform length substantially of CNT.This is provided in the overall joint product large cross-sectional area with reliable absorbtion character.The continuation method of the fiber material for the manufacture of CNT injection described in this article, the time of staying of adjustable fiber material in CNT growth room is to control CNT growth and final control CNT length.This provide control grow the means of the special properties of CNT.Also can by regulating carbon raw material and flow rate of carrier gas and controlling reaction temperature CNT length.By controlling such as to realize the other control to CNT character for the preparation of the size of the catalyst of CNT.Such as, 1nm transition metal nanoparticles catalyst can be used especially to provide SWNT.Larger catalyst can be used mainly to prepare MWNT.

In addition, CNT growth method used is applicable to provide the following CNT fiber material injected, it has equally distributed CNT on fiber material, avoid CNT bunchy and/or gathering simultaneously, and wherein preforming CNT suspended or to be scattered in solvent solution and CNT bunchy and/or gathering may occur manual being applied in the technique of fiber material.These CNT assembled tend to faintly adhere to fiber material, and if existing characteristics CNT character, then only faintly show this character.In some embodiments, suppose that diameter is the 5 wall CNT of about 8nm, about 55% can be up to the maximum distribution density that the percentage covering i.e. capped fiber surface area represents.By the space in CNT being considered as " can fill " space, calculate this coverage rate.By changing catalyst decentralization on surface and controlling gas composition and process speed to realize multiple distribution/density value.Usually, for given parameters group, the percentage of coverage in about 10% can be realized on whole fiber surface.Higher density and shorter CNT are applicable to improve engineering properties, and longer CNT and comparatively low-density are applicable to improve thermal property and electrical property, comprise EMI shielding and radar absorption, but the density improved are still favourable.When growing longer CNT, comparatively low-density can be obtained.This may be because of higher temperature and grow faster, causes lower catalyst particle productive rate.

The CNT being applicable to be injected into fiber material comprises single wall CNT, double-walled CNT, many walls CNT and its mixture.Definite CNT consumption depends on the final use of the composite material of shielding EMI.Except EMI shielding and radar absorption, CNT also can be used for thermal conductance and/or conductance application.In some embodiments, the carbon nano-tube of injection is single-walled nanotube.In some embodiments, the carbon nano-tube of injection is many walls nanotube.In some embodiments, the carbon nano-tube of injection is the combination of single wall and many walls nanotube.The characteristic properties of single-walled nanotube and many walls nanotube has some differences, for some final uses of fiber, and the nanotube of this or another kind of type of regulation synthesis.Such as, single-walled nanotube can be semiconductor or metal nano-tube, and many walls nanotube is metal nano-tube.Therefore, if the EM radiation absorbed by convert to such as can with the signal of telecommunication of Computer systems, so may need control CNT type.

CNT provides its characteristic properties to the fiber material that CNT injects, such as mechanical strength, middle low-resistivity, high heat conductance etc.Such as, in some embodiments, the resistivity of the fiber material of carbon nano-tube injection can lower than the resistivity of independent matrix fiber material.More generally, the degree that the fiber degree that shows these characteristics that gained CNT injects can be covered by carbon nano-tube along with carbon fiber and density and become.These character also can transfer to the composite material of the whole shielding EMI introducing it.Suppose 5 wall MWNT of 8nm diameter, the fiber surface area (this calculating be also considered as in the space in CNT can fill) of any amount of the 0-55% of fiber can be covered.This numerical value is lower for the CNT of small diameter, and is larger for larger-diameter CNT.55% surface area coverage is equivalent to about 15,000 CNT/ micron ².Can to depend on that the mode of CNT length gives carbon fibre material with other CNT character.The length of the CNT injected can change in the scope between about 1 micron to about 500 microns, comprise 1 micron, 2 microns, 3 microns, 4 microns, 5 microns, 6 microns, 7 microns, 8 microns, 9 microns, 10 microns, 15 microns, 20 microns, 25 microns, 30 microns, 35 microns, 40 microns, 45 microns, 50 microns, 60 microns, 70 microns, 80 microns, 90 microns, 100 microns, 150 microns, 200 microns, 250 microns, 300 microns, 350 microns, 400 microns, 450 microns, 500 microns, and all values therebetween.Such as, CNT length also can be less than about 1 micron, comprises about 0.5 micron.CNT also can be greater than 500 microns, comprises such as 510 microns, 520 microns, 550 microns, 600 microns, 700 microns and all values therebetween.Shield application for some EMI, the length of described CNT can change between about 100nm is to about 25 microns.For the application that pure EMI shields, the length of CNT can change between about 100nm is to about 500 μm.Can be that the CNT of about 1 micron to about 10 microns introduces the present invention and shields in the composite material of EM by length.Such CNT length is also applicable in the application improving shear strength.The length of CNT also can be about 5 to about 70 microns.If arrange described CNT in machine direction, so such CNT length is applicable in the application of hot strength raising.The length of CNT also can be about 10 microns to about 100 microns.Such CNT length is applicable to raising electrical property/thermal property and engineering properties.The method injected for CNT also can provide length to be the CNT of about 100 microns to about 500 microns, and it also can be conducive to improving electrical property and thermal property, comprises radar absorption and EMI shields.Therefore, the fiber material that described CNT injects is multi-functional and can strengthens other character many of the composite material of whole shielding EMI.Therefore, in some embodiments, comprise and can have the different homogeneous area of multiple CNT length to realize different destination properties by the composite material of fiber material that injects of the CNT of coiling length.Such as, with can expecting to have the CNT uniform length of the carbon fibre material that CNT injects shorter in the Part I strengthening shear strength character, and identical can winding material CNT uniform length longer with the Part II strengthening EMI screening effectiveness and/or radar absorption character.Can such as at least partially, be strengthened to realize machinery by the shorter CNT as mentioned above that has arranging the composite material of shielding EMI at the fiber material of CNT injection.Described composite material can adopt the form of following skin, and it has longer CNT for shielding EM radiation on the composite material surface of shielding EMI, and side is provided with shorter CNT for mechanical enhancer under the surface.The control easily realized CNT length by regulating carbon raw material and inert gas flow velocity and change linear velocity and growth temperature.This can change identical can coiling length fiber material different piece in CNT length, or different bobbin can be adopted, and described different bobbin is introduced into the suitable part of composite construction.

The composite material of shielding EMI of the present invention comprises host material to form the composite material with the fiber material that CNT injects.Such host material such as can comprise epoxides, polyester, vinyl esters, Polyetherimide, PEKK, polyphthalamide, polyether-ketone, polyether-ether-ketone (polytheretherketone), polyimides, P-F and bismaleimides.Be applicable to host material of the present invention and can comprise any known base material (see Mel M.Schwartz, Composites Handbook (composite material handbook) (the 2nd edition, 1992)).Host material more generally can comprise resin (polymer), comprises thermosetting and thermoplastic resin, metal, pottery and cermet.

Be suitable for the thermosetting resin making host material and comprise phthalic acid/maleic acid type polyester, vinyl acetate, epoxides, phenolic resins, cyanate, bismaleimides and Na Dike (nadic) capped polyimides (such as PMR-15).Thermoplastic resin comprises polysulfones, polyamide, Merlon, polyphenylene oxide, polysulfide, polyether-ether-ketone, polyether sulfone, polyamide-imides, Polyetherimide, polyethylene, polypropylene, polyimides, polyarylate and liquid crystal polyester.

Be suitable for the metal making host material and comprise aluminium alloy, such as aluminium 6061,2024 and 713 aluminum bronze weldering.Be suitable for the pottery making host material and comprise carbon ceramics, such as lithium aluminosilicate, oxide, such as aluminium oxide and mullite, nitride, such as silicon nitride, and carbide, such as carborundum.Be suitable for the cermet making host material and comprise carbide-base ceramics (tungsten carbide, chromium carbide and titanium carbide), refractory metal pottery (tungsten-thorium oxide and barium-carbonate-nickel), chromium-aluminium oxide, nickel-magnesium oxide iron-zirconium carbide.Arbitrary above-mentioned host material all can be used alone or combinationally uses.Pottery and metal-matrix composite such as can be used for thruster vector control surface or use in other high temperature application of EMI shielding character, electronic box such as, in high temperature application used.

In some embodiments, the composite material of described shielding EMI also can comprise multiple transition metal nanoparticles.In some embodiments, these transition metal nanoparticles can be used as the potential catalyst from CNT growth step and exist.Without being bound by theory, serve as CNT and form the transition metal NP of catalyst by forming CNT growth crystal seed structure and catalysis CNT growth.Described CNT forms the base portion that catalyst can be retained in fiber material, if there is protective coating, then by optional protective coating (existence of protective coating depend on fiber material type used and usually such as carbon and metallic fiber) locking, and be injected into the surface of fiber material.Under these circumstances, the crystal seed structure formed by transition metal nanoparticles catalyst is at first enough to be used in extending non-catalytic crystal seed CNT growth, and does not allow catalyst to move along CNT growth leading edge, as in the prior art often seen by.In this case, NP serves as the tie point of CNT to fiber material.There is protective coating also can cause other indirect binding pattern to carry out CNT injection.Such as, CNT can be formed catalyst and be locked in protective coating as above, but not contact with fibrous material surface.In this case, obtain protective coating to be arranged on CNT and to form stacked structure between catalyst and fiber material.In either case, formed CNT is injected into fiber material.In some embodiments, some protective coatings will allow CNT growth catalyst to followed by the leading edge of the nanotube in growth.In these cases, this can cause CNT be directly incorporated into fiber material or be optionally directly incorporated into protective coating.No matter the character of the actual binding pattern formed between carbon nano-tube and fiber material, the CNT of injection is firm and the fiber material allowing CNT to inject display carbon nanotube properties and/or characteristic.

Under unshielded coating exists, potential CNT growth particle can come across base portion, the nanotube ends, therebetween arbitrary place and mixing thereof of carbon nano-tube.In addition, CNT is injected fiber material can be directly or pass through the transition metal nanoparticles of intervention and be indirectly.In some embodiments, potential CNT growth catalyst comprises Fe nanometer particles.These Fe nanometer particles can have different oxidation state, such as, comprise Zero-valent Iron, iron (II), iron (III) and its mixture.There is the EMI shield property that can contribute to whole composite material from the potential formation of iron based nanoparticles of CNT growth further.

In some embodiments, the fiber that described CNT injects can pass iron, ferrite or formation of iron based nanoparticles solution after growth.The a large amount of Fe nanometer particles of CNT Absorbable rod, it can contribute to EMI shielding further.Therefore, this additional treatment step provides complementarity Fe nanometer particles to improve EM radiation absorption.

The present invention shields the EM radiation that wide wave spectrum is contained in the composite material Absorbable rod of EM and/or reflection, and described wide wave spectrum comprises the wave spectrum containing radar frequency band.In some embodiments, described composite material Absorbable rod and/or reflect high-frequency radar.In the frequency of high frequency (HF) the radar scope between about 3 to about 30MHz (10-100m).This radar is applicable to the radar application of shore radar and over-the-horizon radar (OTH).In some embodiments, described composite material Absorbable rod and/or reflected P band radar.This comprises the radar frequency being less than about 300MHz.In some embodiments, described composite material Absorbable rod and/or reflect the radar of very high frequency band (VHF).The frequency of VHF radar about 30 in the scope about between 330MHz.VHF wave band is applicable to very long-range application, comprises the application of penetrated surface.In some embodiments, the radar of described composite material Absorbable rod hyperfrequency (UHF) wave band.UHF waveband is included in about 300 to the frequency in the scope about between 1000MHz.The application of UHF waveband comprises very long-range application, the application of such as ballistic missile early warning system, penetrated surface and camouflaged target identification (foliage penetrating).In some embodiments, described composite material Absorbable rod and/or long (L) band radar of reflection.L-band is included in about 1 to the frequency in the scope about between 2GHz.L-band is applicable to remote application, such as, comprise air traffic control and supervision.In some embodiments, described composite material Absorbable rod and/or reflect short (S) band radar.S-band is included in about 2 to the frequency in the scope about between 4GHz.S-band is applicable to following application, such as Terminal Air Traffic Control, long term weather and marine radar.In some embodiments, described composite material Absorbable rod and/or reflection frequency about 4 to the C-band radar in the scope about between 8GHz.C-band is used in satellite transponder and Climate application.In some embodiments, described composite material Absorbable rod and/or reflection frequency about 8 to the X-band radar of the scope about between 12GHz.X-band is applicable to the application of such as missile guidance, marine radar, weather, intermediate-resolution drawing and ground surveillance.In some embodiments, described composite material Absorbable rod and/or reflection are included in about 12 to the K-band radar of the frequency about between 18GHz.K-band can be used for cloud detection by worker in meteorology, and adopts K-band radar gun by police and for detecting over-speed vehicles.In some embodiments, described composite material absorbs and/or reflection is included in about 24 to the K of the frequency about between 40GHz _aband radar.K _awave band can be used for optical radar, such as, in order to trigger those optical radars of camera shutter under traffic signals.

In some embodiments, described composite material absorb and/or reflection widely about 40 to millimeter (mm) band radar about between 300GHz.Mm wave band comprise in military communication about 40 to the Q-band about between 60GHz, for the oxygen in air absorb by force about 50 to the V-band about between 75GHz, about 60 to the E wave band about between 90GHz, be used as experiment automotive vehicle, high-resolution meteorological observation and imaging vision sensor about 75 to the W-waveband about between 110GHz, and for through-wall radar and imaging system about 1.6 to the UWB wave band about between 10.5GHz.

In some embodiments, in K-band, the SE of described composite material at about 90dB to about between 110dB.In some embodiments, in X-band, the SE of described composite material at about 90dB to about between 100dB.In some embodiments, in C-band, the SE of described composite material at about 80dB to about between 90dB.In some embodiments, in S-band, the SE of described composite material at about 70dB to about between 80dB.In some embodiments, in L-band, the SE of described composite material at about 50dB to about between 60dB.Figure 15 to 18 shows the EMI shielding result being configured to the shielding exemplary panel of EMI according to the present invention.Such as, the scope build-in test panel 220 (Figure 15) between 0.1MHz to 18GHz.

As mentioned above, screening effectiveness (SE) is for evaluating the EM radiation absorption of composite material and/or a kind of means of albedo that shield EMI of the present invention.SE measured EM absorb and/or reflecting material to the attenuation degree of electromagnetic field.SE is the electromagnetic signal strength before shielding and the difference after shielding between its intensity.Measure attenuation rate/SE with decibel (dB), it corresponds to the ratio between the field intensity under having and existing without absorption/reflection material.Signal strength signal intensity or amplitude reduce with range index usually, and decibel range follows logarithmic scale.Therefore, attenuation rate 50dB represents that shielding intensity is ten times of 40dB.Usually, low-level is provided to shield about 10 to the shielding in the scope about between 30dB.Shielding between 60 and 90dB is considered as high level shielding, and the shielding between 90 to 120dB is considered as " extraordinary ".

The Reduction Level measuring EMI shielding can be depending on particular mask application, but the routine techniques of test shielding intensity comprises open field test (open field test), coaxial transmission thread test (coaxial transmission line test), shielding box test (shielded box test) and shielded enclosure test (shielded room test).Open field test is designed to the normal service conditions of as far as possible strictly simulation electronic device.Do not having in the region of metal material except testing equipment, placing antenna in the distance different from device.This usually occurs in spacious place and measures to allow the free space of radiation field intensity and conducted emission.By detect produce the noise level table record result of EMI level.Usually open field test is used for finished electronic product.

Coaxial transmission thread test be a kind of measurement plane wave field electromagenetic wave radiation to measure the method for the screening effectiveness of planar materials, and it is generally used for comparative test.To be placed in special storage unit with reference to experimental rig and to record its voltage received at multiple frequencies.Then replace the first subjects with load device, make it experience the test of same train.Comparison between reference and load device determines the ratio between the power had and receive under no shielding material.

Shielding box test employing has the seal box of perforate (cut-out) part.The screen unit that conductibility is coated with is placed on above cartridge apertures, and measures the transmitting of all transmissions and reception.Record and compare the electromagnetic signal inside and outside from box, the ratio table wherein between signal shows screening effectiveness.

In some cases, the amount of the ambient noise reduced in region can be challenging.In these cases, shielded enclosure can be adopted to test.This test is usually directed at least two shielded enclosures and the transparent wall of transducer therebetween.Experimental rig and testing equipment are put in a Room, and sensor array is put in another room.Shielding can be comprised plumbous with the possibility reducing the measure error caused by external signal.Shielded enclosure test is applicable to the magnetic susceptibility (susceptibility) of evaluating apparatus very much.

In some embodiments, the test method evaluating screening effectiveness can be the Standardization Act of the open reference technology that the use described in IEEE-STD-299 improves.Test in compartment (partitioned chamber), the side of described compartment provides EM transmission source and the other parts of compartment provide receiving equipment.

In some embodiments, described composite material comprises CNT, and its existence range is about 1 % by weight to about 7 % by weight of the composite material of described shielding EM radiation.In some embodiments, CNT load can between about 1 % by weight to about 20 % by weight of the composite material of described shielding EMI.In some embodiments, CNT load in the composite material of described shielding EMI can be 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19% and 20% of the weight of the composite material of described shielding EMI, comprises any mark between these values.Described shielding EMI composite material in CNT load also can be less than 1%, comprise such as about 0.1% to about between 1%.The CNT load of composite material of described shielding EMI also can be greater than 20%, comprises such as 25%, 30%, 40% etc. to about 50% and all values therebetween.

In some embodiments, the composite material of shielding EMI comprises the carbon fibre material that carbon nano-tube (CNT) is injected.The carbon fibre material that this CNT injects can comprise the carbon fibre material that can be wound around dimension, around the protective coating of the conformal setting of carbon fibre material, and is injected into the carbon nano-tube (CNT) of carbon fibre material.CNT is injected into carbon fibre material and can comprises the binding pattern independent CNT being directly incorporated into carbon fibre material or indirectly being combined by transition metal NP, protective coating or carry out both it.

The carbon fibre material that CNT of the present invention injects can comprise protective coating.Protective coating such as can comprise the alkoxy silane be spun on glass and glass nano-particles, methylsiloxane, aikyiaiurnirsoxan beta (alumoxane), alumina nanoparticles.CNT can be formed catalyst to be added in uncured barrier material, and then put on carbon fibre material together.In other embodiments, before deposition CNT forms catalyst, barrier material can be added in carbon fibre material.Barrier material can have enough thin to allow CNT to form catalyst exposure in carbon raw material to carry out the thickness of follow-up CVD growth.In some embodiments, this thickness is less than or approximates the effective diameter that CNT forms catalyst.In some embodiments, the thickness of protective coating is in about 10nm to scope about between 100nm.Protective coating also can be less than 10nm, comprises 1nm, 2nm, 3nm, 4nm, 5nm, 6nm, 7nm, 8nm, 9nm, 10nm and any value therebetween.

Without being bound by theory, described protective coating can serve as the intermediate layer between carbon fibre material and CNT, and the machinery of CNT can be provided to inject to carbon fibre material.This machinery injects and also provides firm system, wherein by carbon fibre material as the platform organizing CNT simultaneously still to give CNT character to carbon fibre material.In addition, the benefit comprising protective coating is that it provides protection to carbon fibre material immediately, in order to avoid by being exposed to chemical damage that moisture causes and/or by for heating any fire damage that carbon fibre material causes under promoting the temperature of CNT growth.

When growing CNT on carbon fibre material, the high temperature that may exist in reative cell and/or any residual oxygen and/or moisture can damage carbon fibre material.In addition, carbon fibre material itself can to react and impaired because forming catalyst itself with CNT.That is, under the reaction temperature of synthesizing for CNT, carbon fibre material can be equivalent to the carbon raw material of catalyst.This excessive carbon can disturb the controlled introducing of carbon feeding gas and even by making catalyst excess load carbon and poisoning.Protective coating used in the present invention is designed to the CNT synthesis promoted on carbon fibre material.Without being bound by theory, this coating can provide thermal boundary (thermal barrier) to thermal degradation and/or can be the physical barriers preventing carbon fibre material to be exposed to environment under high temperature.Alternatively or additionally, it can be minimized in CNT and form contact surface area between catalyst and carbon fibre material and/or it can alleviate carbon fibre material at CNT growth temperature and is exposed to CNT and forms catalyst.

There is the carbon fiber of following three types, it is classified according to the precursor for generation of fiber, and wherein any one all can be used in the present invention: artificial silk (Rayon), polyacrylonitrile (PAN) and pitch (Pitch).Carbon fiber from the rayon precursors as cellulosic material has the carbon content of relatively low about 20% and fiber tends to have low strength and stiffness.Polyacrylonitrile (PAN) precursor provide carbon content be about 55% carbon fiber.Because blemish is minimum, therefore based on the hot strength of the carbon fiber of PAN precursor usually above the carbon fiber based on other carbon fiber precursor.

Pitch precursor based on petroleum asphalt, coal tar and polyvinyl chloride also can be used for manufacturing carbon fiber.Although the cost of pitch is relatively low and carbon productive rate is relatively high, problem uneven in given batch may be there is.

In some embodiments, the fiber material that described CNT injects comprises glass fiber material.The glass fiber material that CNT injects without the need to introducing protective coating as above, but optionally adopts protective coating.Type of glass used in glass fiber material can be any type, such as, comprise E type glass, A type glass, E-CR type glass, C type glass, D type glass, R type glass and S type glass.E type glass comprises the aluminium borosilicate glass that has and be less than 1 % by weight alkali metal oxide (alkali oxide) and is mainly used in GRP.A type glass comprises alkali metal-lime (alkali-lime) glass with few or non-oxidation boron.E-CR type glass comprises aluminium-lime silica salt of having and being less than 1 % by weight alkali metal oxide and acid resistance is high.C type glass comprises the alkali metal-soda lime glass with high oxidation Boron contents and such as staple glass fibre.D type glass comprises borosilicate glass and has high dielectric constant.R type glass comprise not containing MgO and CaO sour sial salt glass and there is high mechanical strength.S type glass comprises and does not contain CaO and do not have the alumina silicate glass of high content of MgO and have high hot strength.One or more in these type of glass can be worked in above-mentioned glass fiber material.In certain embodiments, described glass is E type glass.In other embodiments, described glass is S type glass.

In some embodiments, if the fiber material that described CNT injects comprises ceramic fibre material, so identical with the situation of glass, optionally use protective coating when using ceramic fibre material.The Types of Pottery used in ceramic fibre material can be any type, such as, comprise oxide, such as aluminium oxide and zirconia, carbide, routine boron carbide, carborundum and tungsten carbide, and nitride, routine boron nitride and silicon nitride.Other ceramic fibre material such as comprises boride and silicide.Ceramic fibre also can comprise basalt fiber material.Ceramic fibre material can exist with the form of the composite material with other fiber type.Such as, the dry goods ceramic fibre material also introducing glass fibre can often be found.

In some embodiments, the fiber material that described CNT injects comprises metallic fiber material, and in other execution mode, and what described CNT injected fiber material comprises organic fibrous material.One of skill in the art will recognize that any fiber material all can be used for EMI shielding application in and selected definite fiber material can be depending on integrally-built final application.Such as, during the EMI that ceramic fibre material can be used for using with high temperature association by those of ordinary skill in the art shields.

The fiber material that described CNT injects can comprise based on following fiber material: long filament, yarn, tow, tape, fibrous braid, fabric, non-woven fibre pad, fiber plies yarn and other 3D fabric construction.Long filament comprises the high aspect ratio fiber of diameter in the size range of about 1 micron to about 100 microns.The bundle of the long filament of the normally compact combination of fibre bundle and usually twist together to obtain yarn.

Yarn comprises the bundle of the stranded long filament of combining closely.Each filament diameter in yarn is relatively uniform.Yarn there is different weight, this weight is described as their ' Tekes ', represent the weight of 1000 linear meter(lin.m.)s, unit is gram), or danier (denier), represent 10, the weight of 000 yard, unit is pound, and typical Tekes scope is usually between about 200 Tekes to about 2000 Tekes, but this value will depend on definite fiber material used.

Tow comprises the bundle of the not stranded long filament of loose combination.As in the yarn, the filament diameter in tow is normally uniform.Tow also there is Different Weight and Tekes scope usually between 200 Tekes and 2000 Tekes.Its feature is thousand numbers of long filament in tow usually, such as 12K tow, 24K tow, 48K tow etc.These values are different from the type of fiber material used again.

Tape can be assembled into the material that fabric maybe can represent the smooth tow of nonwoven.Tape can have different in width and normally be similar to the two sides structure of band (ribbon).Method of the present invention with carry out CNT in one or both sides of tape and inject compatible.The tape that CNT injects can be similar to " carpet " or " covering " on flat base surface.And, method of the present invention can be implemented with the bobbin functionalization by tape with continuous mode.

Fibrous braid represents the rope class formation of the carbon fiber of dense accumulation.Such as can assemble these structures from yarn.Basketwork structure can comprise hollow space or can assemble basketwork structure around another core.

In some embodiments, a large amount of majority fibers material structure can be organized into fabric or sheet structure.Except above-mentioned tape, it such as also comprises fabric, non-woven fibre pad and fiber plies yarn.Can from these senior ordered structures of assembling such as matrix tow, yarn, long filaments, wherein CNT has injected matrix fiber.Alternatively, these structures can be used as the substrate of described CNT method for implanting herein.

Fig. 1-6 shows TEM and the SEM image of the CNT prepared on the carbon fibre material prepared by described method herein.Hereafter with in example Ι-Ι Ι Ι be described in further detail the step preparing these materials.These figure and step illustrate the method for carbon fibre material, but persons of ordinary skill in the art will recognize that and can adopt other fiber material when significantly not departing from these methods, such as enumerate above those.Fig. 1 and Fig. 2 respectively illustrates the TEM image of many walls and the double-walled carbon nano-tube prepared on AS4 carbon fiber with continuous processing.Fig. 3 shows and will be formed after the nano-particle catalyst of CNT mechanically injects carbon fibre material surface, scanning electron microscopy (SEM) image of the CNT grown from protective coating.Fig. 4 shows following SEM image, and it is presented at the consistency of distribution of lengths in 20% of the target length of about 40 microns of the CNT that carbon fibre material grows.Fig. 5 shows display protective coating to the SEM image of the impact of CNT growth.When applying protective coating, the well-arranged CNT that growth is fine and close, and when not applying protective coating, do not grow CNT.Fig. 6 shows the low magnification ratio SEM of the CNT on carbon fiber, which show the CNT density uniformity on whole fiber in about 10%.

Refer now to Fig. 7, it schematically illustrates the viewgraph of cross-section of the composite material 100 according to some execution modes of the present invention.Composite material 100 is applicable to manufacture the EMI shielding construction of the EM radiation shielding characteristics with expectation, such as the case panel of electric assembly.Composite material 100 comprises plurality of fibers or long filament 110, such as, in the tow that can exist in matrix 140 or rove.Fiber 110 is injected with carbon nano-tube 120.In an illustrative embodiments, fiber 110 can be glass (such as E type glass, S type glass, D type glass) fiber.In another embodiment, fiber 110 can be carbon (graphite) fiber.Also other fiber can be used, such as polyamide (aromatic polyamides, aromatic polyamide) (such as Kevlar 29 and Kevlar 49), metallic fiber (such as steel, aluminium, molybdenum, tantalum, titanium, copper and tungsten), a tungsten carbide, ceramic fibre, metal-ceramic fiber (such as aluminium silicon dioxide), cellulose fibre, polyester, quartz and carborundum.The CNT synthesis of any fiber type is can be used for herein about the CNT synthesis technique described in carbon fiber.In some embodiments, before applying catalyst particle, with suitable protective coating coating metal fiber, to prevent the chemical reaction such as alloying occurred between catalyst particle and metallic fiber undesirably.Therefore, when adopting metallic fiber material, described method can be similar to the method for carbon fibre material.Similarly, thermal sensitivity aramid fibre also can adopt protective coating to protect fiber material from the impact of representative temperature used during CNT growth.

In an illustrative embodiments, carbon nano-tube 120 vertically can grow usually from the outer surface of fiber 110, thus provides radial covering to each individual fibers 110.Carbon nano-tube 120 can on fiber 110 growth in situ.Such as, can make glass fibre 110 charging by maintain about 500 DEG C to 750 DEG C to the growth room under fixed temperature.Then can introduce in growth room by carbon-containing feeding gas, wherein under catalyst nanoparticles exists, carbon-based group dissociates and causes and forms carbon nano-tube on the glass fibers.

In one structure, in order to produce composite material 100, the fiber 110 that CNT injects is delivered to resin bath.Another structure in, can from CNT inject fiber 110 braided fabric and subsequently by fabric delivery to resin bath.Resin bath can contain any resin of the composite material 100 for the manufacture of the fiber 110 and matrix 140 comprising CNT injection.In one structure, matrix 140 can adopt the form of epoxy matrix material.In another structure, matrix 140 can be general purpose polyester (such as phthalic acid polyester), the polyester (such as isophthalic polyester) improved, phenolic resins, bismaleimides (BMI) resin, one of polyurethane and vinyl acetate.Matrix 140 also can adopt the application examples that is applicable to need to implement at higher operating temperatures as the form of the non-resin matrix (such as ceramic substrate) of Aero-Space and/or Military Application.Should be understood that matrix 140 also can adopt the form of metal matrix.

Known method for composite material can be applied, such as, for the fiber 110 that injects with resinous substrates infiltration CNT or the vacuum assisted resin injection method of fabric woven thus and resin extruded method.Such as, the fiber 110 that CNT can be injected or its fabric are laid in a mold and can to its resin by injections.In another structure, the fiber 110 that CNT can be injected or its fabric are laid in a mold, are then vacuumized by described mould with tractive resin through mould.In another structure, can by being wound around the fiber 110 injected with " 0/90 " orientation braiding CNT.Such as, this can realize as follows: in first direction such as vertical direction, be wound around the ground floor of fiber 100 or panel that CNT injects, then with first direction into about the second direction such as horizontal direction of 90 ° in be wound around the second layer or the panel of the fiber 100 that CNT injects.This " 0/90 " orientation can give other structural strength to composite material 100.

The fiber 110 injected by carbon nano-tube 120 can be introduced thermoset plastics matrix (such as epoxy matrix material) 140 to produce composite material 100.Known method fiber introduced in matrix in prior art.In one structure, matrix 140 introduced by the fiber 110 that high-pressure curing method can be used to be injected by CNT.The CNT load of composite material represents the percentage by weight of the carbon nano-tube in given composite material.Method for the manufacture of CNT based composites known in the state of the art relate to make loose (namely not with can the fiber of coiling length be combined) carbon nano-tube is directly mixed in the resin/matrix of initial composite material.Due to the factor that such as prohibitive viscosity improves, the composite material therefore produced by these methods can be limited to the maximum of about 5 % by weight carbon nano-tube in finished composite material.On the other hand, composite material 100 can have the CNT load more than 25 % by weight, as described above.When use CNT inject fiber 110, shown CNT load up to 60 % by weight composite material.The EM shielding character of material depends on its conductivity.The whole conductivity of composite material 100 partly changes with the CNT load of composite material 100.Therefore, the screening effectiveness of composite material 100 partly changes with the CNT load of composite material 100.

The above-mentioned composite material 100 wherein introducing the fiber having CNT to inject is applicable to manufacture following assembly, and it has electromagnetic radiation, comprises radar shielding character, shields application for numerous EMI.Show the electromagnetic radiation in the effective absorption of composite material 100 and/or reflected radar wave spectrum, comprise the radiation of infrared ray (about 700nm to about 15cm), visible ray (about 400nm to about 700nm) and ultraviolet (about 10nm to about 400nm).

The composite construction such as expected because of its weight and strength characteristics is not suitable for manufacture electronic device assembly, sometimes because its EMI shielding relative mistake.Such as, some fibre composite material usually sends EM radiation and therefore has the EMI shielding character of relative mistake.Glass fiber compound material is such as normally transparent in wide EM radiation wave spectrum.It also has dielectricity in essence and has poor electrical conductance and thermal conductance.CNT is introduced the EM absorptive rate of radiation that glass fiber compound material effectively improves gained composite material.The EMI shielding of improvement benefited from by carbon fibre composite by the good EM radiation reflective be provided in particular frequency range.Carbon fibre material is introduced CNT and strengthens EMI shielding in carbon fibre composite by the reflection of the absorption at least partially or improvement that provide EM radiation in addition.Such as, when absorbing, subsequently can by energy trasfer to electrical ground.Therefore the composite material 100 with the fiber 110 that CNT injects strengthens EMI shielding character, and retain the characteristic relevant to composite material expected, the ratio of such as weight and intensity is low simultaneously.Example as shown in Figure 16 to 18, by regulating the percentage by weight of carbon nano-tube in composite material with the usefulness regulating composite material to shield EM radiation.

Refer now to Fig. 8, schematically illustrate the viewgraph of cross-section of the fiber material 200 that CNT injects.Fiber material 200 optionally comprises matrix.No matter whether there is host material, all the fiber material 200 that CNT injects can be applied to the surface of the composite material previously manufactured, with the EM shielding character of remarkable reinforced composite.In some embodiments, prefabricated composite material self can show poor EMI shielding.But the fiber material arranging CNT injection in its surface can give the EM screening ability of enough degree to provide good EMI shielding.The fiber material 200 that can inject around prefabricated Filament Wound Composite or braiding CNT.In some embodiments, if before being arranged on composite material by host material, host material had not previously had the fiber material 200 that CNT injects, then can add after being arranged on described composite material again.In addition, the host material therefore added can have the matrix identical with preformed material or similar characteristic to facilitate strong combination.

The fiber material 200 that CNT injects comprises multiple fiber at fiber material 210, such as tow or rove.Carbon nano-tube 120 is injected fiber material 210.Van der Waals force between the carbon nano-tube 120 of bunch (group) that closely place can make the interaction between CNT 120 enlarge markedly.In some embodiments, this can cause the CNT " staggered engage " of carbon nano-tube 120, and this can provide long filament to be combined with long filament or gluing.In an illustrative embodiments, can by applying the staggered joint of pressure further induced carbon nanotube 120 with fiber material 200 consolidation (consolidate) making CNT inject to fiber material 210.This long filament is combined the formation that can promote fibre bundle, tape and fabric under existing without resinous substrates with long filament.Relative to the long filament-resin-bonded that such as can be used in conventional fibre tow composite material, this long filament is combined with long filament also can improve and shears and hot strength.The complex fiber material that the fibre bundle injected by these CNT is formed shows outer (out-of-axis) intensity of the interlaminar shear strength of good EMI shielding character and raising, hot strength and axle.

In some embodiments, described CNT engages without the need to special intactly interlocking to improve EM shielding character.Such as, permeation pathways is produced by the single-contact between CNT.In such execution mode, " loose " CNT relation can provide less or rarer electric pathway, or does not have the closed-loop path of clear and definite end points.This can provide the discrete electrical path being beneficial to EM absorption characteristic, because it provides the permittivity of varying level in the material for catching the EM radiation in overall structure.

In one structure, can the fiber material 200 that CNT injects be applied on the surface of conventional composites materials such as glass fibre composite panel or carbon fiber composite panel as coating, to give good EMI shielding character to this conventional composites materials.In one structure, the fiber material 200 that CNT can be injected is wound around around composite construction with the EMI shielding character strengthening composite construction.The coating of matrix such as resinous substrates can be applied to one or more layers CNT inject fiber material 200 or fabric woven thus on, be applied to composite material surface, the composite fibre 200 injected to protect CNT is from the impact of external environment condition.Fiber material that multi-layer C NT injects can be set to provide multiple CNT orientation, length and density to change EM radiation absorption characteristics, to absorb EM radiation in different frequency range and absorption from the EM radiation impacting this integrally-built source with different angles.

Refer now to Fig. 9, schematically illustrate the coating of fiber material 210, it is provided with the CNT of injection on the upper surface 355 of composite material 350.Such as, composite material 350 can adopt the form of conventional compound glass or GRP.In another structure, composite material 350 can adopt the form of carbon fiber composite structure or carbon fibre reinforced plastic structure.Composite material 350 self is not suitable for the application needing good radar absorption or EMI shielding character usually.But, by applying coating or the layer 230 of the fiber material 210 it being injected with CNT on the surface 355 of composite material 350, the radar absorption that this combination (that is, the combination of the fiber of composite material 350 and CNT injection) display significantly strengthens or EMI shielding character.In an illustrative embodiments, fiber 210 can be the fibre bundle being injected with carbon nano-tube 220 and matrix such as resinous substrates.In another illustrative embodiments, can braided fiber 210 to form following fabric, it can put on the upper surface 355 of composite material 350.

In some embodiments, the fiber material 200 of CNT injection can be woven to form fabric.In one structure, in the scope of the about 12.5mm of the fiber that about 20 nanometers (nm) of the fiber that the thickness of fiber coat can inject at individual layer CNT be injected to multilayer CNT.Although exemplified execution mode for simplicity depicts single layer fibre, it should be understood that, multi-layer fiber also can be used to form coating on composite material 350.

The advantage of the fiber material 200 using CNT to inject is, this coating can combinationally use with the conventional composites materials of EMI shielding character difference, retains the advantage of composite material simultaneously, the ratio of such as weight and intensity and other machinery expected and architectural characteristic.

The layer of fiber material 200 or coating that CNT injects can be set on the surface of composite construction to strengthen the EMI shielding character of composite construction.The layer of fiber material 200 that the CNT putting on conventional composites materials injects or this purposes of coating contribute to using conventional composites materials to carry out manufacturing and without the need to the processing of complexity.

Refer now to Figure 10, illustrate the coating system 400 according to an illustrative embodiments.System 400 receives the fiber 110 that CNT injects from upstream fiber source.In an illustrative embodiments, the fiber that CNT can be injected is from wherein by carbon nano-tube 120, the growth room injected fiber material is directly directed to coating system 400.The fiber 110 that CNT injects be impregnated in the fiber 110 that the contained chemical solution 420 of bath 410 injects to process CNT further.The fiber 110 guiding CNT to inject by two deflector rolls 440,450.The fiber 110 that CNT injects is impregnated into solution 420 by bath roller 430.In an illustrative embodiments, solution 420 is formation of iron based nanoparticles solution.In one structure, solution 420 comprises the iron-based solute of 1 part of volume in 200 parts of hexane solvents.Carbon nano-tube 120 on the fiber 110 that CNT injects will absorb Fe nanometer particles, thus the radar absorption of the further fiber 110 strengthening CNT injection and any composite material manufactured thus or EMI shielding character.Should be understood that the broadband fabric that can process fiber 110 manufacture of injecting from CNT is similarly to introduce formation of iron based nanoparticles.

In some embodiments, the composite material of described shielding EM radiation can have the CNT be infused in a controlled manner on fiber material.Such as, CNT can grow around the individual fibers element of fiber material in the mode of fine and close radial arrangement.In other embodiments, the CNT after can processing growth is further directly to arrange along fiber axis.Such as, this is by machinery or chemical technology or by applying electric field and realizing.

Because described CNT can have the orientation relative to fiber axis of regulation, so CNT can have controlled orientation again in any overall composite construction manufactured thus.This is by arbitrary above-mentioned winding and/or textile processes, or is realized by the orientation that controls the fiber material that CNT injects in solidification resinous substrates etc.

Therefore, in some embodiments, the invention provides a kind of method manufacturing the composite material of these shieldings EMI, the method comprises 1) host material as lower part in arrange CNT inject fiber material, the orientation of the fiber material that the CNT of this part in host material injects is controlled, with 2) host material is solidified, the controlled tropism control of the fiber material of wherein CNT injection the relative orientation of the CNT that it injects.Method for composite material includes but not limited to wet type and dry type filament winding, fiber placement, hand lay and resin injection.These methods can in order to produce panel, part, assembly and/or structure to improve EMI SE.

In some embodiments, the invention provides a kind of panel, it comprises the composite material that the present invention shields EMI.In some embodiments, panel can be obtained and be suitable for and be used for the electronic installation that EMI shields and engage.The panel with the fiber material that CNT injects has the controlled CNT of orientation in composite material.This panel can be equipped with following mechanism, and it regulates it relative to the angle of the impact incidence angle of continuous EM radiation transmission source, to maximize EMI shielding.Such as, any EM radiant energy absorbed all is convertible into the signal of telecommunication, and the described signal of telecommunication and Computer systems shield to maximize EMI with the orientation changing panel.In some embodiments, in detector applies, EM shielding material also can be used for absorbing EM radiation, wherein needs the EM radiation signal effectively obtaining reflection.

As described briefly above, the fiber material that the present invention uses continuous CNT method for implanting to inject to produce CNT.Described method comprises (a) on the surface of fiber material that can be wound around dimension, arranges carbon nano-tube formation catalyst; (b) direct synthesizing carbon nanotubes on carbon fibre material, thus the fiber material forming carbon nano-tube injection.Other step can be used according to the type of fiber material used.Such as, when using carbon fibre material, the step introducing protective coating can be increased in the method.

For the system of 9 feet long, the linear velocity of described method can in the scope of about 1.5ft/ minute to about 108ft/ minute.The fiber material that the linear velocity realized by method described herein allows the CNT forming commercial correlative with short manufacturing time to inject.Such as, under the linear velocity of 36ft/ minute, the amount (exceeding 5 % by weight of the CNS injected on fiber) of fiber that CNT injects can exceed material 100 pounds or more manufactured by following system every day, and this system is designed to process 5 independent tow (20 pounds/tow) simultaneously.System to manufacture immediately or manufactures more tow at faster speed by the vitellarium by repeating.In addition, as known in the prior art, some steps manufactured in CNT slow down speed inhibition, thus prevent continuous operation mode.Such as, in typical process known in the prior art, implementing CNT formation catalyst reduction step can expend 1-12 hour.CNT growth itself also may be consuming time, such as, need several tens minutes to carry out CNT growth, thus hampers the Express Order Wire speed realized in the present invention.Method described herein overcomes such rate-limiting step.

The carbon fibre material formation process that CNT of the present invention injects can avoid CNT to tangle, and tangles when managing to there will be CNT when the suspension of preformed carbon nano-tube is put on fiber material.That is, because preformed CNT does not merge with carbon fibre material, CNT tends to bunchy and entanglement.Result is that faintly the gluing CNT in carbon fibre material distributes not too even.But if expected, method so of the present invention provides the entanglement CNT pad of high uniformity on the surface at carbon fibre material by reducing stand density.First the CNT grown at a low density is flow in carbon fibre material.In such execution mode, fiber does not grow enough fine and close in induce vertical arrangement, thus obtains at carbon fibre material the pad that tangles on the surface.By contrast, the preformed CNT of artificial applying does not guarantee CNT pad being uniformly distributed and density on carbon fibre material.

Figure 11 depicts the flow chart of the method 700 for the manufacture of the carbon fibre material injected according to the CNT of exemplary embodiment of the invention.Such as, persons of ordinary skill in the art will recognize that the small variant injecting this method of CNT in example on carbon fibre material all can change, with the fiber material providing other CNT to inject, such as glass or ceramic fibre.Some the such changes of described condition aspect can comprise the step such as cancelled and apply protective coating, and it is optional for glass and pottery.

Method 700 at least comprises following operation:

701: by carbon fibre material functionalization.

702: protective coating and CNT are formed the carbon fibre material that catalyst is applied to functionalization.

704: carbon fibre material is heated to the temperature being enough to carry out carbon nano-tube synthesis.

706: facilitate the mediated CNT growth of the CVD on the carbon fiber of supported catalyst.

In step 701, by carbon fibre material functionalization to promote the moistening of fiber surface and to improve the gluing of protective coating.

In order to carbon nano-tube is injected carbon fibre material, such as, with synthesizing carbon nanotubes on the carbon fibre material of the conformal coating of protective coating.In one embodiment, this realizes in the following way: according to operation 702, by the first conformal coating carbon fibre material with protective coating, on protective coating, then arranges nanotube form catalyst.In some embodiments, can before catalyst deposit partially cured protective coating.This can provide following surface, and it is easy to receive catalyst and allows it to embed in protective coating, comprises and allows to be formed between catalyst and carbon fibre material at CNT to carry out surface contact.In such execution mode, can after being embedded into catalyst complete solidified protection coating.In some embodiments, be coated on carbon fibre material by conformal for protective coating, deposit CNT simultaneously and form catalyst.CNT form catalyst and protective coating one in place, just can solidified protection coating completely.

In some embodiments, can before catalyst deposit complete solidified protection coating.In such execution mode, the carbon fibre material that the process of using plasma body has completely crued protective coating prepares to accept catalyst to make surface.Such as, the carbon fibre material with the plasma treatment of solidified protection coating can provide rough surface, wherein can deposit CNT and form catalyst.Therefore plasma process for " roughening " barrier surface contributes to catalyst deposit.Roughness is in nanoscale usually.In plasma-treating technology, form pit or the depression of the dark and a few nanometer diameter of a few nanometer.Can use to comprise and be not limited to any one in the multiple gas with various of argon gas, helium, oxygen, nitrogen and hydrogen or multiple plasma realizes this surface modification.In some embodiments, also in carbon fibre material itself, directly plasma roughening can be carried out.It is gluing in carbon fibre material that this can contribute to protective coating.

As hereafter composition graphs 11 is described further, described catalyst preparing is become following liquid solution, it contains the CNT formation catalyst comprising transition metal nanoparticles.The diameter of synthesized nanotube is relevant with the size of metallic as above.In some embodiments, the business dispersion that CNT forms transition metal nanoparticles catalyst can be obtained, dilution is not added to it and just uses, in other embodiments, can the business dispersion of dilute catalyst.Whether dilute these solution and can be depending on the density and length of waiting the expectation growing CNT as mentioned above.

With reference to the illustrative embodiments of Figure 11, show carbon nano-tube synthesis based on chemical vapour deposition (CVD) (CVD) technique and at high temperature carry out described synthesis.Actual temp becomes with selected catalyst, but by usual in the scope of about 500 to 1000 DEG C.Therefore, operate 704 to relate to and the carbon fibre material with protective coating is heated to temperature in above-mentioned scope with a carbon nanotubes synthesis.

In operation 706, on the carbon fibre material of supported catalyst, then implement the nanotube growth that CVD facilitates.CVD method is facilitated by such as carbon-containing feeding gas such as acetylene, ethene and/or ethanol.CNT synthetic method uses inert gas (nitrogen, argon gas, helium) as main carrier gas usually.Carbon raw material is provided in the scope of about 0% to about 15% of total mixture.By preparing the environment of the inertia substantially for CVD growth from growth room's removing moisture and oxygen.

In described CNT synthetic method, form the position growth CNT of transition metal nanoparticles catalyst at CNT.Produce the existence of the electric field of strong plasma optionally for affecting nanotube growth.That is, growth is tended to follow direction of an electric field.By suitably regulating the geometry of plasma spraying and electric field, the CNT (namely vertical with carbon fibre material) of vertical arrangement can be synthesized.Under given conditions, even under existing without plasma, nanotube closely of being separated by will maintain vertical-growth direction, thus obtain the fine and close CNT array being similar to carpet or covering.There is the directivity that protective coating also can affect CNT growth.

By spraying or dip-coating solution or carry out vapour deposition by such as plasma process and realize the operation arranging catalyst on carbon fibre material.The selection of technology can be coordinated with the pattern applying protective coating.Therefore, in some embodiments, being formed in a solvent after catalyst solution, by with the carbon fibre material of described spray solution or dip-coating protective coating or by spraying and the combination of dip-coating, applying catalyst.The arbitrary technology be used alone or in combination all can adopt once, twice, three times, four times until any number of times, to provide the carbon fibre material forming catalyst even spread fully with CNT.When adopting dip-coating, such as, carbon fibre material can be put in the first dipping bath, in the first dipping bath, continue for first time of staying.When employing the second dipping bath, carbon fibre material can be put in the second dipping bath, continue for second time of staying.Such as, according to dipping structure and linear velocity, carbon fibre material can be formed in catalyst solution at CNT and process about 3 seconds to about 90 seconds.Adopt and spray or dipping process, obtaining catalyst surface density is be less than the carbon fibre material of about 5% surface coverage to as high as about 80% coverage rate, and wherein CNT forms catalyst nanoparticles is almost individual layer.In some embodiments, technique carbon fibre material being coated with CNT formation catalyst should obtain individual layer at the most.Such as, CNT formed catalyst stacking on CNT growth can weaken CNT and inject the degree of carbon fibre material.In other embodiments, can use as transition-metal catalyst is deposited on carbon fibre material by under type: evaporation technique, electrolytic deposition technology, with other technique known to persons of ordinary skill in the art, such as, transition-metal catalyst is added in plasma feeding gas with the form of the composition of metal organic salt, slaine or other promotion gas-phase transport.

Because method of the present invention is designed to continuous print, thus can in a series of bath the reelable carbon fibre material of dip-coating, wherein dip-coating bath spatially separate.Regenerating wherein in the continuation method of initial carbon fiber, the dipping bath of CNT formation catalyst or sprinkling can be the first step after following steps: applied and solidification or partially cured on carbon fibre material by protective coating.For the new carbon fibre material formed, protective coating can be applied and CNT forms catalyst to replace applying sizing agent.In other embodiments, after protective coating under other sizing agent exists, CNT can be formed catalyst and puts on the new carbon fiber formed.CNT forms catalyst and this of other sizing agent applies simultaneously, still can provide and form catalyst to guarantee that CNT injects with the CNT of the protective coating surface contact of carbon fibre material.

Used catalyst solution can be transition metal nanoparticles, and it can be any d district as above transition metal.In addition, described nano particle can comprise in element form or the alloy of d district metal of salt form and its mixing and non-alloyed mixture.These salt forms include but not limited to oxide, carbide and nitride.Non-restrictive illustrative transition metal NP comprises Ni, Fe, Co, Mo, Cu, Pt, Au and Ag and its salt and composition thereof.In some embodiments, directly apply by CNT being formed catalyst or flow into carbon fibre material, carrying out protective coating deposition simultaneously, and such CNT formation catalyst is set on carbon fiber.Many in these transition-metal catalysts are easy to from multiple supplier, comprise such as luxuriant and rich with fragrance NTK company (Bedford, NH) commercially available.

The catalyst solution putting on carbon fibre material for CNT being formed catalyst can be formed in any common solvent of catalyst whole dispersion equably allowing CNT.These solvents can include but not limited to water, acetone, hexane, isopropyl alcohol, toluene, ethanol, methyl alcohol, oxolane (THF), cyclohexane or have controlled polarity to produce other solvent any that CNT forms the suitable dispersion of catalyst nanoparticles.CNT forms the concentration of catalyst can in the scope of the catalyst of about 1:1 to 1:10000 and solvent.When to apply protective coating and CNT forms catalyst simultaneously, also such concentration can be used.

In some embodiments, carbon fibre material can be heated with synthesizing carbon nanotubes under the temperature after deposition CNT forms catalyst between about 500 DEG C and 1000 DEG C.Can introducing carbon raw material with before carrying out CNT growth or substantially with its simultaneously, heat at these tem-peratures.

In some embodiments, the invention provides a kind of following method, it comprise from carbon fibre material removing sizing agent, above carbon fibre material conformal applying protective coating, to apply to carbon fibre material CNT form catalyst, carbon fibre material is heated at least 500 DEG C and on carbon fibre material synthesizing carbon nanotubes.In some embodiments, the operation of described CNT injection technology comprises from carbon fibre material removing sizing agent, protective coating is put on carbon fibre material, CNT is formed catalyst and put on carbon fiber, fiber be heated to CNT synthesis temperature and CVD facilitates on the carbon fibre material of supported catalyst CNT growth.Therefore, when adopting business carbon fibre material, from the discontinuous step of carbon fibre material removing sizing agent before the method for carbon fiber that structure CNT injects can be included in and carbon fibre material arranges protective coating and catalyst.

The step of synthesizing carbon nanotubes can comprise a lot of technology forming carbon nano-tube, is included in those technology disclosed in the U.S. Patent application US 2004/0245088 of common pending trial, by described patent application by reference to being incorporated herein.The CNT grown on fiber of the present invention realizes by technology known in the prior art, and described technology includes but not limited to the CVD technology of microcavity, heat or plasma enhancing, laser ablation, arc discharge and high pressure carbon monoxide (HiPCO).During CVD, especially, top can be directly used to be provided with the carbon fibre material with protective coating of CNT formation catalyst.In some embodiments, the sizing agent of any routine can be removed before CNT synthesis.In some embodiments, acetylene gas ionization is synthesized for CNT to produce one cold carbon plasma.To the carbon fibre material directing plasma of carried catalyst.Therefore, in some embodiments, carbon fibre material synthesizes CNT to comprise (a) and form carbon plasma; (b) carbon plasma is guided on the catalyst be arranged on carbon fibre material.The diameter of the CNT grown is described by the size of CNT formation catalyst as above.In some embodiments, the fibrous substrate of starching is heated between about 550 to about 800 DEG C to promote that CNT synthesizes.In order to cause CNT growth, make in two kinds of gas inflow reactors: process gas is argon gas, helium or nitrogen such as, and carbonaceous gas such as acetylene, ethene, ethanol or methane.The site growth CNT of catalyst is formed at CNT.

In some embodiments, described CVD growth is plasma enhancing.Plasma is produced by providing electric field during growth course.The CNT grown under these conditions can follow direction of an electric field.Therefore, by regulating the geometry of reactor, can around the carbon nano-tube that arranges of cylindrical fiber radial growth of vertical ground.In some embodiments, the radial growth around fiber does not need plasma.For carbon fibre material such as tape, mat, fabric, the folded yarn etc. with not ipsilateral, catalyst can be arranged on one or both sides, and correspondingly, CNT also can grow in one or both sides.

As mentioned above, the speed of continuous processing is provided to implement CNT synthesis with the functionalization be enough to for carbon fibre material can be wound around.Many Instrument structures promote this continuous synthesis, example as follows.

In some embodiments, the carbon fibre material that CNT injects can be constructed in " congruent gas ions " (all plasma) technique.Congruence ionomer technology can be: plasma described above by carbon fibre material roughening to improve fiber surface wet characteristic, with more conformal protective coating is provided, and as follows by mechanical interlocking and chemistry gluing and improve coating adhesive viscosity: by being used in given activity gaseous matter such as oxygen, nitrogen, hydrogen in argon gas or helium class plasma by carbon fibre material functionalization.

The product that the carbon fibre material with protective coating is injected to form final CNT by multiple further plasma-mediated step.In some embodiments, congruent ionomer technology can be included in the second time surface modification after protective coating solidification.This is the plasma process that a kind of surface of the protective coating on " roughening " carbon fibre material deposits with promoting catalyst.As mentioned above, can use and include but not limited to the plasma of any one or more in the multiple gas with various of argon gas, helium, oxygen, ammonia, hydrogen and nitrogen and realize surface modification.

After surface modification, proceed catalyst to the carbon fibre material of protective coating to apply.This is a kind of plasma process forming catalyst for depositing CNT on fiber.CNT forms catalyst transition metal normally as above.Can transition-metal catalyst be added in plasma feeding gas as the precursor of following form: ferrofluid, metallorganic, slaine or promote other composition of gas-phase transport.Can at room temperature vacuum be neither being needed or not again to apply catalyst in the surrounding environment of inert atmosphere.In some embodiments, before catalyst applies, carbon fibre material is cooled.

Continue described congruent ionomer technology, carbon nano-tube synthesis occurs in CNT growth reactor.This realizes by using the chemical vapour deposition (CVD) of plasma enhancing, is wherein sprayed onto on the fiber of supported catalyst by carbon plasma.Because there is carbon nano tube growth under high temperature (depending on catalyst, usually in the scope of about 500 to 1000 DEG C), can before being exposed to carbon plasma the fiber of heating load catalyst.For described method for implanting, optionally heat carbon fibre material until it softens.After heating, carbon fibre material prepares to receive carbon plasma.Such as by making carbonaceous gas such as acetylene, ethene, ethanol etc. through the electric field that can ionize this gas, produce carbon plasma.By nozzle, this cold carbon plasma is guided to carbon fibre material.Carbon fibre material can be in close proximity to nozzle, such as, within about 1 centimetre, nozzle, to receive plasma.In some embodiments, heater is arranged on above carbon fibre material and sentences in plasma atomizer the high temperature maintaining carbon fibre material.

Another structure synthesized for continuous carbon nano-tube relates to a kind of special rectangular reactor, and it for directly synthesizing and carbon nano-tube on carbon fibre material.Reactor can be designed in online continuously (in-line) technique of the fiber manufacturing carrier band carbon nano-tube.In some embodiments, by chemical vapour deposition (CVD) (" CVD ") technique, under the high temperature in multi-region reactor (multi-zone reactor) at atmosheric pressure and within the scope of about 550 DEG C to about 800 DEG C, grow CNT.The fact occurring to synthesize at atmosheric pressure facilitates a factor in Continuous maching line reactor being introduced CNT synthesis on fiber.Process another consistent advantage with using the on-line continuous in this region reactor (zone reactor) to be, within the several seconds (a seconds), CNT growth occurs, this is contrary with several minutes (or longer) in other step typical in prior art and Instrument structure.

CNT synthesis reactor according to multiple execution mode comprises following characteristics:

the synthesis reactor of rectangular configuration:the cross section of typical CNT synthesis reactor known in the prior art is circular.This has many reasons, such as, comprise: historical reasons (usually using cylindrical reactor in laboratory) and convenience (easily hydrodinamical model, heater system being easy to hold round tube (quartz etc.) in cylindrical reactor) and easily manufacture.Deviate from cylindrical convention, the invention provides a kind of CNT synthesis reactor with rectangular cross section.This reason deviated from is as follows: 1. because many carbon fibre materials can processed by reactor are opposite planar, such as, as plane tape or sheet form, so circular cross section uses the poor efficiency of reactor volume.This poor efficiency causes cylindrical CNT synthesis reactor to have some defects, such as, comprise, a) maintain enough system purifications; The reactor volume increased needs the gas flow rate increased to maintain the gas purification of phase same level.This causes for the system manufacturing CNT poor efficiency a large amount of in open environment; B) the carbon feed stream increased; According to above-mentioned a), the relative increase of inert gas needs the carbon feed stream increased.Consider that the volume of 12K carbon fibre tow is 1/2000 of the cumulative volume of the synthesis reactor with rectangular cross section.In the columnar growth reactor (namely width holds the barrel type reactor that shakeout carbon fibre material identical with rectangular cross section reactor) of equivalence, the volume of carbon fibre material is 1/17 of chamber volume, 500.Although gas aggradation technique such as CVD is only stressed usually and temperature domination, volume has significant impact to deposition efficiency.Still there is excess volume in rectangular reactor.This excess volume facilitates undesired reaction; But the volume of cylindrical reactor is the about octuple of described volume.Due to the chance of this larger generation competitive reaction, therefore desired reaction more effectively can occur in cylindrical reactor chamber.The exploitation that CNT growth this slows down for continuous processing is problematic.A benefit of rectangular reactor structure is, reduces reactor volume by using little rectangular chamber height, to make this volume ratio better and to make reaction more effective.In certain embodiments of the present invention, the cumulative volume of rectangle synthesis reactor is greater than the cumulative volume about 3000 times at the most through the carbon fibre material of synthesis reactor.In some other execution modes, the cumulative volume of rectangle synthesis reactor is greater than the cumulative volume about 4000 times at the most through the carbon fibre material of synthesis reactor.In other execution mode other, the cumulative volume of rectangle synthesis reactor is greater than cumulative volume through the carbon fibre material of synthesis reactor less than about 10000 times.Additionally, notably, when using cylindrical reactor, compared with the reactor with rectangular cross section, need more carbon feeding gas to provide identical flow percentage.Should be understood that synthesis reactor has following cross section in some other execution modes, it is by relatively similar with it and describe relative to the polygonal in form that the reactor with circular cross section provides similar reactor volume to reduce not for rectangle; C) problematic Temperature Distribution; When using the reactor of relative minor diameter, minimum to the temperature gradient of its wall from chamber center.But along with such as increasing being used for the extensive size manufactured, temperature gradient increases.These temperature gradients cause product quality to change (that is, product quality becomes with radial position) in whole carbon fibre material substrate.When use has the reactor of rectangular cross section, substantially avoid this problem.Especially, when using planar substrates, along with size of foundation base scale is amplified, height for reactor can remain constant.Temperature gradient between reactor head and bottom can be ignored substantially, and therefore avoids caused heat problem and product quality change.2. gas is introduced: because prior art adopts tube furnace usually, so typical CNT synthesis reactor is at one end introduced gas and made it pass reactor come the other end.In some disclosed in this article execution modes, can symmetrically through side or by the top board of reactor and base plate, the heart or introduce gas in target growth district in the reactor.This can improve whole CNT growth speed, because the hottest part of the feeding gas continuous supplementation system entered, this is that CNT growth enlivens part most.This constant gas make-up is the importance of the growth rate of the increase shown by rectangle CNT reactor.

subregion.there is provided the hangs of relatively cool purifying area at the two ends of rectangle synthesis reactor.Applicant determines, if hot gas and external environment condition (that is, outside reactor) mix, so the degraded of carbon fibre material will increase.Cool purifying area provides buffering between built-in system and external environment condition.Typical CNT synthesis reactor structure known in the prior art cools substrate with usually needing careful (and slow).Achieve at the cool purifying area in the exit of rectangle CNT growth reactor of the present invention and cool in short time period, needed for for continuous on-line machining.

non-contact type hot wall metallic reactors.in some embodiments, the hot wall reactor be particularly made up of stainless steel of metal is adopted.This violation intuition that may seem, because metal and particularly stainless steel are comparatively easy to Carbon deposition (that is, cigarette ash and accessory substance are formed).Therefore, most of CNT reactor structure uses quartz reactor, because Carbon deposition is less, quartz is more easy to clean and quartz contributes to sample observation.But applicant observes, the cigarette ash increased on stainless steel and Carbon deposition produce more consistent, faster, more effective and more stable CNT growth.Without being bound by theory, show, be combined with operate atmospherically, the CVD technique diffusion limited implemented in the reactor.That is, catalyst is " glut "; Due to its relatively high dividing potential drop (situation when operating under partial vacuum higher than reactor), carbon too much therefore can be obtained in reactor assembly.Therefore, in open system, in particularly clean open system, too much carbon can adhere to catalyst particle, thus damages the ability of its synthesis CNT.In some embodiments, when reactor time " dirty ", expressly runs rectangular reactor because depositing cigarette ash on metal reaction wall.Once Carbon deposition becomes the individual layer on reactor wall, then carbon is convenient to be deposited on above self.Because some can obtain carbon because of this mechanism " being drawn out of ", so all the other the carbon raw materials in group (radical) form can not make speed and the catalyst reaction of catalyst poisoning.Existing system meeting " cleanly " runs, if it is open to Continuous maching, so produces much lower CNT productive rate by under the growth rate reduced.

Although as mentioned above to carry out CNT synthesis normally favourable for " dirty " formula, when cigarette ash produces blocking, specific part such as the gas collecting main (manifold) and import of instrument but meeting negative effect CNT growth method.In order to overcome this problem, available cigarette ash suppresses coating such as silicon dioxide, aluminium oxide or MgO to protect this type of region of CNT growth reative cell.In fact, these parts of instrument can suppress in coating in these cigarette ash in dip-coating.Metal such as can be used for these coatings, because INVAR has similar CTE (thermal coefficient of expansion), thus guarantee that coating is suitably gluing at relatively high temperatures, thus prevent cigarette ash to be significantly accumulated in key area.

the catalyst reduction of combination and CNT synthesis.in CNT synthesis reactor disclosed in this article, catalyst reduction and CNT growth both occur in reactor.This is important, because if implement as discontinuous operation, so reduction step can not realize enough in time in continuous processing.In typical process known in the prior art, implement reduction step and usually expend 1-12 hour.At least in part due to carbon feeding gas is introduced reactor center, but not picture uses the fact usually introducing end in the prior art of cylindrical reactor, and therefore two kinds of operations all occur in reactor according to the present invention.Reduction process is there is when fiber enters the thermal treatment zone; So far, gas if having time and wall reaction and causing before redox (being interacted by hydrogen group) cool down with catalyst reaction.It is this transitional region wherein occurring to reduce., there is CNT growth, occur maximum growth rate at the near gas inlets place close to reactor center in the hottest isothermal region in systems in which.

In some embodiments, when the carbon fibre material such as carbon filament bundle adopting loosely to be connected, continuous processing can comprise the expansion line stock (strand) of tow and/or the step of long filament.Therefore, such as, because by tow unwinding (unspool), so the fiber development system based on vacuum can be used to be launched.When adopt can the starching carbon fiber of relative stiffness time, other heating can be adopted with " softening " tow to promote that fiber launches.The expansion fiber comprising independent long filament enough can launch the whole surface area exposing long filament, therefore allows tow more effectively to react in subsequent process steps.This expansion can make between close about 4 inches to about 6 inches of whole 3k tow.The surface treatment step of carbon filament bundle by being made up of plasma system described above launched.After by protective coating applying also roughening, then the fiber of expansion forms catalyst dipping bath by CNT.Obtain the radial carbon filament bundle fiber being distributed with catalyst particle on the surface.Then catalysis loading wire bundle fiber enters suitable CNT growth room, rectangular chamber such as mentioned above, wherein the flow process by atmospheric pressure CVD or PE-CVD technique is used for synthesizing CNT under up to the speed of some microns per second.The bunch fiber now with the CNT of radial arrangement leaves CNT growth reactor.

In some embodiments, the carbon fibre material that CNT injects is by another treatment process, and described treatment process is for the plasma process by CNT functionalization in some embodiments.Can by other CNT functionalization in order to promote that it is to the adhesivity of specific resin.Therefore, in some embodiments, the invention provides the carbon fibre material of the CNT injection with functionalization CNT.

As the part of Continuous maching that can be wound around carbon fibre material, the carbon fibre material that CNT injects also by starching dipping bath with apply may be favourable in the final product any other sizing agent.If expect that wet type is wound around final, the carbon fibre material that so CNT injects can pass resin bath and be wrapped on mandrel or bobbin.CNT locks on carbon fibre material by gained carbon fibre material/resin combination, thus allows process relatively easily and manufacture composite material.In some embodiments, CNT injection is used for the filament winding providing improvement.Therefore, the carbon filament bundle CNT that carbon fiber such as carbon filament bundle are formed being injected through resin bath with the CNT producing resin impregnated.After resin impregnated, by delivery head, carbon filament bundle is positioned on the surface of rotary core shaft.Then can with definite geometrical pattern, tow be wound on mandrel in a known manner.

Above-mentioned winding method provides pipe (pipe), cylinder (tube) or other form as manufactured by formpiston characteristic.But the form be made up of winding method disclosed herein is different from those that manufactured by the filament winding method of routine.Particularly, in method disclosed in this article, described form is made up of the composite material comprising CNT injection tow.These forms therefore by the tow benefited from as injected by CNT the intensity etc. of enhancing that provides.

In some embodiments, CNT is injected into the linear velocity that the continuation method that can be wound around on carbon fibre material can realize between about 0.5ft/ minute to about 36ft/ minute.CNT growth room is 3 feet long and in execution mode that is that operate under 750 DEG C of growth temperatures wherein, and the method can with the linear velocity operation of about 6ft/ minute to about 36ft/ minute, with Production Example as the CNT of length between about 1 micron to about 10 microns.Described method also can be run, with Production Example as the CNT of length between about 10 microns to about 100 microns by the linear velocity of about 1ft/ minute to about 6ft/ minute.Described method also can be run, with Production Example as the CNT of length between about 100 microns to about 200 microns by the linear velocity of about 0.5ft/ minute to about 1ft/ minute.CNT length is not only relevant with linear velocity and growth temperature, but the flow velocity of carbon raw material and inert carrier gas also can affect CNT length.Such as, will make the length of CNT between 1 micron to about 5 microns by the flow velocity that 1% carbon raw material forms that is less than in inert gas under high linear speed (6ft/ minute to 36ft/ minute).To make the length of CNT between 5 microns to about 10 microns by the flow velocity formed more than 1% carbon raw material in inert gas under high linear speed (6ft/ minute to 36ft/ minute).

In some embodiments, can be passed through described method more than a kind of material with carbon element to run simultaneously.Such as, multiple tape tow, long filament, line stock etc. can in parallel through described methods.Therefore, the carbon fibre material of the prefabricated bobbin of any number can be wound around at the end of the method in parallel through described method again.The number of winding carbon fibre material of parallel running can comprise one, two, three, four, five, six until any number that can be held by the width of CNT growth reative cell.In addition, when multiple carbon fibre material is by described method, the number of collection bobbin can be less than bobbin number when the method starts.In such execution mode, carbon line stock, tow etc. can be made by these carbon fibre materials being combined into other technique of high grade carbon fiber material such as fabric etc.Such as, described continuation method also can introduce aft-loaded airfoil shredding machine, and it contributes to the chopped mat forming CNT injection.

The inventive method CNT being injected fiber material allows the CNT length controlling to have uniformity, and allows in a continuous process to be wound around fiber material CNT functionalization at the high velocities.When the material time of staying is between 5 to 300 seconds, can at the arbitrary value from about 0.5ft/ minute in about 36ft/ minute or larger scope for the linear velocity in the continuation method of the systems of 3 feet long.Selected speed depends on the multiple parameters as hereafter explained further.

In some embodiments, the material time of staying of about 5 seconds to about 30 seconds can produce the CNT of length between about 1 micron to about 10 microns.In some embodiments, the material time of staying of about 30 seconds to about 180 seconds can produce the CNT of length between about 10 microns to about 100 microns.In other execution mode, the material time of staying of about 180 seconds to about 300 seconds can produce the CNT of length between about 100 microns to about 500 microns.Persons of ordinary skill in the art will recognize that these scopes are approximate and CNT length also can be regulated by reaction temperature and carrier and carbon material concentration and flow velocity.

In some embodiments, the invention provides following shielding conductor, it comprises carbon nano-structured (CNS) screen, described screen is included in the CNS material in host material, described CNS screen be monolithic and be arranged on around dielectric layer and wire, wherein dielectric layer is arranged between described CNS screen and described wire.In some embodiments, the substitute of the metal forming and/or braid of described CNS screen as being typically used as EMI screen in prior art is provided.

Typical braid shielded thing, such as, seen in coaxial cable those, although effectively provide EMI to shield under lower frequency ranges, along with frequency increases and more and more poor efficiency.The usefulness reduced is due to the gap in fabric at least partly, and this gap permission RF energy is seepage by braid shielded thing.The gap stayed in fabric is described by optics coverage rate percentage usually.Braid is better, and optics coverage rate is better.

In order to the usefulness relaxed at higher frequencies reduces, by high end cable, usual metal forming or the Mylar that aluminizes, supplementing as braid shielded thing.The tape of foil material is generally used for providing the optics coverage rate of almost 100%.Tape be stranded on, therefore produce seam, it makes coverage rate be less than 100%.Layers of foil can be monolithic, as shown in Figure 21, or covers independent line pair, as shown in Figure 22.Use these materials can increase complexity and cost for cables manufacturing.

By by CNS material as in polymer such as PTFE, PVC and Mylar, EMI screen can be produced, by described EMI screen and cable cover(ing) or the internal layer that is easy to apply integrated, manufacture to rationalize and reduce costs.For radioshielding, the thermoplastic resin of working load CNS can replace using paper tinsel and metallization tape completely.Except other advantage, replace metal forming can contribute to alleviating cable weight.In some embodiments, can eliminate completely the use of paper tinsel and the thermoplastic resin of load C NS is used in existing extrusion type oversheath by increasing thin internal layer to insulating outer protective cover, thus the cable of new class is provided.In some embodiments, the disclosure provides a kind of and manufactures the method with the cable cover(ing) of dual (duel) purposes.Such as, by adding CNS in the thermoplastic resin blocked water, cable can either shield EMI, again can water resistant.

Refer now to Figure 19, show the shielding conductor 1900 according to an illustrative embodiments.Shielding conductor 1900 comprises carbon nano-structured (CNS) screen 1910 be arranged on around optional dielectric layer 1920 and wire 1930.Figure 20 shows the typical coaxial cable 2000 with metal forming 2010, and the structure of described metal forming is similar to the CNS screen 1910 of Figure 19.According to execution mode disclosed herein, the metal forming 2010 of coaxial cable 2000 can replace with the CNS screen 1910 in such as Figure 19.In addition, the position of the CNS screen 1910 be substituted without the need to be limited in fig. 20 metal forming 2010 there is part.In some embodiments, CNS screen can be the individual course arranged around braid 2020.In some embodiments, CNS screen can be integrated into the layer on the inner surface of oversheath 2030.In some embodiments, CNS screen can be oversheath 2030, and namely oversheath can directly be extruded with CNS material disclosed herein.In other execution mode, more than one CNS screen can be adopted.Such as, in some embodiments, both oversheath 2030 and superseded metal forming 2010 can all comprise CNS screen.In other execution mode again, braid 2020 also can comprise CNS.

Although Figure 19 illustrate only solid conductor 1930, persons of ordinary skill in the art will recognize that CNS screen 1910 can surround the line of any number.Such as, as shown in Figure 21, wire harness 2100 can comprise metal forming 2110, and described metal forming can replace with the CNS screen 1910 such as in Figure 19.And the position of CNS screen needs to be limited to part shown in metal forming 2110 in Figure 21.In some embodiments, CNS screen can be the individual course arranged around braid 2120.In some embodiments, CNS screen can be integrated into the layer on the inner surface of oversheath 2130.In some embodiments, CNS screen can be external jacket 2130, and namely oversheath can directly be extruded with CNS material disclosed herein.In other execution mode, more than one CNS screen can be adopted.Such as, in some embodiments, both oversheath 2130 and superseded metal forming 2110 can all comprise CNS screen.In other execution mode again, braid 2120 also can comprise CNS.

In other other embodiment, Figure 22 shows cable 2200, and it has the paired line of each personal metal forming 2210 parcel.Metal forming 2210 can replace with the CNS screen according to execution mode public above.Therefore, in Figure 22, the position of CNS screen needs to be limited to part shown in metal forming 2210.In some embodiments, described CNS screen can be the individual course arranged around braid 2220.In some embodiments, CNS screen can be integrated into the layer on the inner surface of oversheath 2230.In some embodiments, described CNS screen can be oversheath 2230, and namely oversheath can directly be extruded with CNS material disclosed herein.In other other execution mode, more than one CNS screen can be adopted.Such as, in some embodiments, oversheath 2230 and superseded metal forming 2210 both can comprise CNS screen.In other execution mode again, braid 2220 also can comprise CNS.In some embodiments, the invention provides a kind of cable system, it comprises the CNS implanted layer arranged around twisted wire pair.

In some embodiments, shielding conductor disclosed herein also can comprise the braid shielded thing as shown in Figure 20-22.In some such embodiments, this braid shielded thing can be set around CNS screen.In other embodiments, this braid shielded thing can be arranged between CNS screen and dielectric layer.In other execution mode, this braid shielded thing also comprises the 2nd CNS material.In some embodiments, CNS screen can replace braid shielded thing.

In some embodiments, shielding conductor disclosed herein can use the CNS material comprising the fiber material that CNS injects.In some such embodiments, the fiber material that described CNS injects comprises glass or carbon fiber.In some embodiments, the fiber material that described CNS injects comprises chopped strand.In other embodiments, the fiber material that described CNS injects comprises continuous fiber.In other other execution mode, collected CNS can be compound in thermoplastic resin to form CNS screen.In such execution mode, this CNS should be considered as be different from loose CNT and be characterised in that complicated form mentioned above.In addition, in some embodiments, CNS used herein can comprise the element of Single Walled Carbon Nanotube, double-walled carbon nano-tube, multi-walled carbon nano-tubes or its mixture.Although described CNS structure comprises the element of the CNT of various ways, its because of comprise common wall, crosslinked, branch and its combination complicated form and be different from the array of independent CNT.

According to execution mode disclosed herein, for machinery and conductance and thermal conductance application, the CNS of CNS screen disclosed herein can have a lot of length.Therefore, the length of CNS can change in the scope of about 1 micron to about 500 microns, comprises 1 micron, 2 microns, 3 microns, 4 microns, 5 microns, 6 microns, 7 microns, 8 microns, 9 microns, 10 microns, 15 microns, 20 microns, 25 microns, 30 microns, 35 microns, 40 microns, 45 microns, 50 microns, 60 microns, 70 microns, 80 microns, 90 microns, 100 microns, 150 microns, 200 microns, 250 microns, 300 microns, 350 microns, 400 microns, 450 microns, 500 microns and all values therebetween.Such as, CNT length also can be less than about 1 micron, comprises about 0.5 micron.CNT also can be greater than 500 microns, comprises such as 510 microns, 520 microns, 550 microns, 600 microns, 700 microns and all values and its mark therebetween.

In some embodiments, can by CNS functionalization used in CNS screen.In some such embodiments, functionalization can serve as the means making CNS structure can be covalently bonded in the thermoplastic resin that it is introduced.

In some embodiments, shielding conductor disclosed herein can use the host material comprising thermoplasticity or thermosetting resin, as disclosed herein.In some embodiments, described host material can be polyolefin.In some embodiments, described host material can be polyvinyl chloride (PVC), polyethylene, polypropylene, neoprene, chlorosulfonated polyethylene, thermoplasticity CPE, low smoke and zero halogen, (plenum) of plenum, thermoplastic elastomer (TPE), ethene chlorotrifluoroethylene (ECTFE), polyvinylidene fluoride (PVDF), ETFE (ETFE), fluoropolymer resin-FEP/PFA, Ethylene-Propylene-Diene monomer rubber (EPDM), nylon, polysiloxanes, rubber, polyurethane, porous polyolefin, fluorocarbons, ethylene propylene rubber, crosslinked polyetylene insulated thing (XLPE), or its combination.In the combination that some are such, described host material can be such as to be extruded jointly.In some embodiments, any above-mentioned material also can be cross-linked to expected degree as one of ordinary skill in the understanding.This crosslinking degree can be selected according to destination properties.By means of limiting examples, host material can be advantageously flexible and deformable.In some embodiments, by this resin melting processing, but the process technology of any standard can be adopted.

In some embodiments, described host material is included in heat or the lower contractile thermoplastic resin of UV irradiation.In some embodiments, this contractile thermoplastics can cold events.Contractile thermoplastic resin can such as based on fluoropolymer, such as PTFE, Viton (fluorubber), polyvinylidene fluoride (PVDF), fluorinated ethylene propylene (FEP) (FEP), silicone rubber, PVC and other polyolefine material.In some embodiments, contractile material can based on elastomer.In some such embodiments, this elastomer can be selected from natural polyisoprene: cis 1,4-polyisoprene natural rubber (NR) and trans 1,4-polyisoprene gutta-percha, synthetic polyisoprenes (isoprene rubber is IR), polybutadiene (BR-butadiene rubber), chloroprene rubber (CR), polychloroprene, neoprene (neoprene), neoprene (Baypren), butyl rubber (copolymer of isobutene and isoprene, IIR), halogenated butyl rubber (chlorobutyl rubber CIIR, bromobutyl: BIIR), styrene butadiene rubbers (the copolymer of styrene and butadiene, SBR), acrylonitrile-butadiene rubber (the copolymer of butadiene and acrylonitrile, NBR), also referred to as Buna N rubber, hydrogenated nitrile-butadiene rubber (HNBR) Therban and Zetpol, EPM (ethylene propylene rubber, the i.e. copolymer of ethene and propylene) and EPDM rubber (ethylene propylene diene rubber, i.e. ethene, the trimer of propylene and diene component) epichlorohydrin rubber (ECO), lactoprene (ACM, ABR), silicone rubber (SI, Q, VMQ), fluorosioloxane rubber (FVMQ), fluoroelastomer (FKM and FEPM) Viton, Tecnoflon, Fluorel, Atlas and Dai-El, Perfluoroelastomer (FFKM) Tecnoflon PFR, Kalrez, Chemraz, Perlast, polyether block amide (PEBA), chlorosulfonated polyethylene (CSM), (Hypalon), ethane-acetic acid ethyenyl ester (EVA), thermoplastic elastomer (TPE) (TPE), resilin (resilin), elastin laminin, and polysulfide rubber.

In some such embodiments, described host material comprises the polymer being selected from PETG ester (PET, Mylar), polytetrafluoroethylene (PTFE) and polyvinyl chloride (PVC).One of skill in the art will recognize that other resin be applicable in multiple cable application disclosed herein.In some embodiments, shielding conductor disclosed herein can adopt (CNS) screen comprising material water-proof material in host material.In some such embodiments, host material itself can block water, or can comprise the additive that blocks water together with host material.A kind of exemplary material water-proof material is like this poly-latex.Other additive that blocks water is by and the multiple polymers that comprise in any combining form and homopolymers, polyester, thixotroping P-90-Gel, MP polysiloxanes, propylene hot filler (thermafill), amorphous polyalphaolefin copolymer, nylon, butyl buffer, polyisobutene, pitch and other synthetic resin, synthetic polymer and highly refined mineral oil apparent to those of ordinary skill in the art.

In some embodiments, the invention provides a kind of extrusion type thermoplastic sheath, it comprises CNS material, and described extrusion type thermoplastic sheath is configured to protection at least one line.In line protection application described in being used for by extrusion type thermoplastic sheath of the present invention herein, example is used for EMI shielding, or difunctional namely water-fast with in EMI shielding.In some embodiments, the CNS material that extrusion type thermoplastic sheath disclosed herein can adopt the substrate being shaped with described CNS material from it to collect.In other embodiments, described CNS material is noted on chopped strand.In some such embodiments, described chopped strand comprises glass or carbon.In some embodiments, extrusion type thermoplastic sheath disclosed herein also comprises the additive that blocks water.In some embodiments, extrusion type thermoplastic sheath can have the size being suitable for single line, wire harness, the wire harness comprising dielectric coat etc.

In some embodiments, the available shape being configured to non-wire work and providing EMI to shield provides extrusion type thermoplastic sheath.Therefore, in some embodiments, the invention provides a kind of thermoplastic article, it comprises fiber material and the flexible thermoplastic resin of CNS injection, described flexible thermoplastic resin comprises at least one be selected from PETG ester (PET, Mylar), polytetrafluoroethylene (PTFE) and polyvinyl chloride (PVC).Because these thermoplastic resins are highly flexible, such as, so be easy to the goods obtained except shielding conductor, computer module.Goods of the present invention also can be contained in articles for use such as clothes or flexible mechanical joint.In some embodiments, such thermoplastic article also can comprise the additive that blocks water, thus again provides double action to the thermoplastic resin of load C NS.

Embodiment

example I

Present embodiment illustrates and how can inject carbon fibre material to reach the target strengthening EMI shielding character with CNT in a continuous process.

In the present embodiment, the target making the CNT load on fiber maximum is reached.Be that the 34-70012k carbon fibre tow (the lattice Raphael company (Grafil Inc., Sacramento, CA) of Sacramento, California) of 800 is as carbon fiber substrates by Tekes value.The diameter of the independent long filament that this carbon fiber wire is intrafascicular is about 7 μm.

Figure 12 depicts the system 800 for the manufacture of the fiber injected according to the CNT of exemplary embodiment of the invention.System 800 comprise carbon fibre material lay and tension board 805, starching removing and fiber launch board 810, plasma treatment platform 815, protective coating applying unit 820, air-dry 825, catalyst applying unit 830, solvent flashing platform 835, CNT pouring stand 840, fiber bundle board 845, with carbon fibre material storage reel 850, its interrelating property as shown in the figure.

Lay and strain board 805 and comprise laying reel 806 and fastener 807.Lay reel and carbon fibre material 860 is delivered to this technique; By fastener 807, fiber is strained.For this embodiment, under on-line velocity 2ft/ minute, process carbon fiber.

Fiber material 860 is delivered to the starching removing and fiber expansion board 810 that comprise starching removing heater 865 and fiber unwinder 870.On this platform, any " starching " on removing fiber 860.Usually, removing is realized by starching being burnt from fiber.Any one in multiple heater all can be used for this object, such as, comprise infrared heater, Muffle furnace and other non-contact type heating means.Also the removing of starching can chemically be realized.Fiber unwinder by the individual component of fiber separately.Multiple technologies and instrument can in order to launch fiber, such as, above and below the bar of smooth uniform diameter, or above and below the bar of variable diameter, or have radial enlargement groove and above the bar of roller of kneading, above vibrating head etc., and tractive fiber.Fiber is launched strengthen the downstream process usefulness that such as plasma applies, protective coating applies and catalyst applies by exposing more fiber surface area.

Can place multiple starching removing heater 865 throughout fiber unwinder 870, it allows fiber little by little destarch simultaneously and expansion.Routinely laying and tension board 805 and starching removing and fiber are launched board 810 and be used for fiber industry; Those of ordinary skill in the art are familiar with its design and purposes.

Burn the temperature and time needed for starching to become with (1) sizing agent of carbon fibre material 860 and (2) commercial source/characteristic.The conventional starching on carbon fibre material can be removed at about 650 DEG C.At this temperature, 15 minutes can consuming timely be reached to guarantee starching to burn completely.Temperature is brought up to and can reduce the time of burning higher than this ignition temperature.The minimum of starching thermogravimetric analysis being used for measuring particular commodity burns temperature.

Depend on the time of removing needed for starching, suitably, starching removing heater may need not be included in CNT injection technology; But, can carry out individually removing (such as walking abreast).By this way, the inventory without the carbon fibre material of starching can be accumulated and be wound around the fiberline injected for the CNT not comprising fiber removing heater.Then laying and in tension board 805, be wound around the fiber without starching.This production line can operate under higher than the speed comprising the production line that starching removes.

Unsized fiber 880 is delivered to plasma treatment platform 815.For the present embodiment, with ' downstream mode ' apart from the carbon fibre material 1mm distance launched, use atmospheric plasma processes.Gaseous feed comprises 100% helium.

The fiber 885 of plasma enhancing is delivered to protective coating platform 820.In this exemplary embodiment, type siloxane protective coating solution is used for dip-coating structure.Described solution is ' Accuglass T-11Spin-On glass ' (Honeywell Int Inc (the Honeywell International Inc. of New Jersey Moriston be diluted in the dilution rate of volume 40 to 1 in isopropyl alcohol, Morristown, NJ)).On carbon fibre material, the thickness of gained protective coating is about 40nm.Can at room temperature apply this protective coating in environment around.

The carbon fiber 890 of protective coating is delivered to air-dry 825 with by partially cured for the protective coating of nanoscale.Air-dry carbon fiber thermal air current being passed through whole expansion.Temperature used can in the scope of 100 DEG C to about 500 DEG C.

After air-dry, the carbon fiber 890 of protective coating is delivered to catalyst applying unit 830.In the present embodiment, iron oxides CNT is formed catalyst solution and be used for dip-coating structure.Described solution is with the dilution rate of volume 200 to 1 dilution ' EFH-1 ' (luxuriant and rich with fragrance NTK company (Ferrotec Corporation, Bedford, NH) of New Hampshire Bedford) in hexane.Carbon fibre material achieves the catalyst coat of individual layer.' EFH-1 ' nanoparticle concentration before dilution is in the scope of 3-15 volume %.Described ferric oxide nano particles has composition Fe ₂o ₃and Fe ₃o ₄and diameter is about 8nm.

The carbon fibre material 895 of supported catalyst is delivered to solvent flashing platform 835.Air-flow is passed through the carbon fiber of whole expansion by solvent flashing platform.In the present embodiment, air at room temperature can be adopted to flash off all hexanes stayed on the carbon fibre material of supported catalyst.

After solvent flashing, the fiber 895 of supported catalyst finally enters CNT pouring stand 840.In the present embodiment, use the rectangular reactor with 12 inches of vitellariums to apply CVD growth at atmosheric pressure.97.6% of total air flow is inert gas (nitrogen) and other 2.4% is carbon raw material (acetylene).At vitellarium being remained on 750 DEG C.For above-mentioned rectangular reactor, 750 DEG C is relatively high growth temperature, and it can allow to realize the highest growth rate.

CNT inject after, fiber bundle board 845 again harness CNT inject fiber 897.This operates independent single stock of having recombinated, thus the expansion operation carried out at platform 810 of effectively having reversed.

Around storage fibre winding cylinder 850, the fiber 897 that the CNT being wound around harness injects is to deposit.Fiber 897 load about 60 μm of long CNT that CNT injects, then prepare to be used in the composite material of EMI screening ability enhancing.

The fiber 897 that CNT on fibre winding cylinder 850 injects is recoiled panel and injection ring epoxy resins.Then in autoclave, under the pressure of 100psi, at the temperature higher than 250 ℉ for the specific distribution (pfofile) needed for selected epoxy-resin systems, the composite construction that solidification is injected.The composite panel that the CNT of gained injects shows the average EMI SE of 83dB under 2-18GHz, as by Figure 14 No. 132 panel present.

It should be noted that above-mentioned certain operations can implement to isolate with environment under inert atmosphere or vacuum.Such as, if burn starching from carbon fibre material, so fiber and environment can be separated preventing the damage caused by moisture containing toxic emission (off-gassing).For simplicity, in system 800, except the carbon fibre material laying when production line starts and tension and the storage of the fiber at the end of production line, for all operations all provides environment to isolate.

example II

Present embodiment illustrates and how can inject initial glass fiber material for the application needing the EMI shielding character strengthened with CNT in a continuous process.

Figure 13 depicts the system 900 for the manufacture of the fiber injected according to the CNT of exemplary embodiment of the invention.System 900 comprises glass fiber material and lays and fastener system 902, CNT injected system 912 and Filament-wound Machine device 924, and its interrelating property as shown in the figure.

Laying and tension system 902 comprise lays reel 904 and fastener 906.Lay reel fixing fiber bobbin and glass fiber material 901 is delivered to described technique with the linear velocity of 1ft/ minute; By fastener 906, fiber tension is maintained in 1-5 pound.Routinely laying and tension platform 902 are used for fiber industry; Those of ordinary skill in the art are familiar with its design and purposes.

The fiber 905 of tension is delivered to CNT injected system 912.Platform 912 comprises catalyst application system 914 and microcavity CVD base CNT pouring stand 925.

In the present example embodiment, such as catalyst solution is applied by making the fiber 930 of tension pass dipping bath 935 by impregnation technology.In the present embodiment, use by the catalyst solution formed with volume basis 1 part of ferrofluid nano-particle solution and 200 parts of hexanes.Under the target of CNT injection fiber is the processing line speed improving ILSS, fiber will retain 30 seconds in dipping bath.Can at room temperature vacuum be neither being needed or not again to apply catalyst in the surrounding environment of inert atmosphere.

Then the glass fibre 907 of supported catalyst enters following CNT pouring stand 925, and it is made up of gas purification district after inert gas purge district, CNT growth district and growth before cool growth.Before room temperature under nitrogen being introduced growth, purifying area is with the exhaust of cooling from CNT growth district as above.By quick nitrogen purge, exhaust is cooled to lower than 350 DEG C to prevent fiber oxidation.Fiber enters CNT growth district, and wherein high-temperature heating introduces the 98% quality inert gas (nitrogen) at center and the mixture of 2% quality carbon-containing feeding air-flow (acetylene) by gas collecting main.In the present embodiment, system length is 2.5 feet long and temperature in CNT growth district is 750 DEG C.Make the fiber of supported catalyst be exposed to CNT growth environment 60 seconds in the present embodiment, thus make 60 microns long and the CNT of 2.5 volume % is injected into fiberglass surfacing.The glass fibre finally making CNT inject is through growth after-purification district, and it at 350 DEG C, cool fiber and exhaust is oxidized to prevent fiber surface and CNT.

Filament-wound Machine device 924 is collected the fiber 909 that CNT injects, then prepares to use it in any one in the multiple application needing to improve EMI screening ability.

Fiber 909 wet-wound injected by CNT is on the framework using epoxy resin.This framework is used for for gained panel is with 0 ° and 90 ° of orientations fibers.When by Filament-wound Machine on panel time, in heating chamber press in pressure 200psi and temperature higher than under 250 ℉, cured composite material under for the specific Temperature Distribution of epoxy-resin systems used.As by Figure 15 shown in No. 220 panels, have CNT more than 6.5% in the composite % by weight time, between 2-18GHz, gained panel obtains the average EMI SE of the improvement of 92dB.

Should be understood that the only example the present invention of above-mentioned execution mode, and those of ordinary skill in the art can design many variants of above-mentioned execution mode when not departing from the scope of the invention.Such as, in this manual, provide numerous detail to provide detailed description to exemplary embodiment of the invention and understanding.But, persons of ordinary skill in the art will recognize that can when do not have in those details one or more, or by other technique, material, component etc., implement the present invention.

In addition, in some cases, be not shown specifically or describe known structure, material or operation, fog to avoid each side making illustrative embodiments.Should be understood that each execution mode shown in figure is exemplary, and need not draw in proportion." execution mode " mentioned in whole specification or " execution mode " or " some execution modes " refers to, be included at least one embodiment of the present invention by associating the special characteristic, structure, material or the characteristic that describe with one or more execution mode, and need not to be in all execution modes.Therefore, the statement " in one embodiment " that multiple position occurs in whole specification, " in embodiments " or " in some embodiments " need not all refer to identical execution mode.In addition, specific feature, structure, material or characteristic can be combined in any suitable manner in one or more execution mode.Therefore be intended to such variant is included in the scope of following claims and its equivalent.

Claims (20)

1. one kind comprises the shielding conductor of carbon nano-structured (CNS) screen, described CNS screen comprises CNS material in host material, described CNS screen be monolithic and be arranged on around wire and optional dielectric layer, wherein when described dielectric layer exists, described dielectric layer is arranged between described CNS screen and described wire.

2. shielding conductor according to claim 1, it also comprises braid shielded thing.

3. shielding conductor according to claim 2, wherein arranges described braid shielded thing around described CNS screen.

4. shielding conductor according to claim 2, is wherein arranged on described braid shielded thing between described CNS screen and described dielectric layer.

5. shielding conductor according to claim 2, wherein said braid shielded thing also comprises the 2nd CNS material.

6. shielding conductor according to claim 1, wherein said CNS material comprises the fiber material that CNS injects.

7. shielding conductor according to claim 6, wherein said fiber material comprises glass or carbon fiber.

8. shielding conductor according to claim 6, the fiber material that wherein said CNS injects comprises chopped strand.

9. shielding conductor according to claim 6, the fiber material that wherein said CNS injects comprises continuous fiber.

10. shielding conductor according to claim 1, wherein said host material comprises thermoplasticity or thermosetting resin.

11. shielding conductors according to claim 1, wherein said host material comprises the polymer being selected from PETG ester (PET, Mylar), polytetrafluoroethylene (PTFE) and polyvinyl chloride (PVC).

12. shielding conductors according to claim 1, are wherein configured to coaxial cable by described shielding conductor.

13. shielding conductors according to claim 1, wherein said (CNS) screen also comprises material water-proof material.

14. 1 kinds of extrusion type thermoplastic sheaths, it comprises CNS material, and described extrusion type thermoplastic sheath is configured to protection at least one line.

15. extrusion type thermoplastic sheaths according to claim 14, described CNS material is collected in the substrate being wherein shaped with described CNS material from top.

16. extrusion type thermoplastic sheaths according to claim 14, wherein note described CNS material on chopped strand.

17. extrusion type thermoplastic sheaths according to claim 16, wherein said chopped strand comprises glass or carbon.

18. extrusion type thermoplastic sheaths according to claim 14, it also comprises the additive that blocks water.

19. 1 kinds of thermoplastic articles, it comprises fiber material and the flexible thermoplastic resin of CNS injection, described flexible thermoplastic resin comprises at least one be selected from PETG ester (PET, Mylar), polytetrafluoroethylene (PTFE) and polyvinyl chloride (PVC).

20. thermoplastic articles according to claim 19, it also comprises the additive that blocks water.