CN106350904A - Graphene enhanced preparation method of micro-nano film-like carbon fiber - Google Patents

Graphene enhanced preparation method of micro-nano film-like carbon fiber Download PDF

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CN106350904A
CN106350904A CN201610769980.0A CN201610769980A CN106350904A CN 106350904 A CN106350904 A CN 106350904A CN 201610769980 A CN201610769980 A CN 201610769980A CN 106350904 A CN106350904 A CN 106350904A
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nano
carbon fiber
graphene
membranaceous
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CN106350904B (en
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孙旭阳
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    • DTEXTILES; PAPER
    • D01NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01FCHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F9/00Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments
    • D01F9/08Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments of inorganic material
    • D01F9/12Carbon filaments; Apparatus specially adapted for the manufacture thereof
    • D01F9/14Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments
    • DTEXTILES; PAPER
    • D01NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01FCHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F9/00Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments
    • D01F9/08Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments of inorganic material
    • D01F9/12Carbon filaments; Apparatus specially adapted for the manufacture thereof
    • D01F9/14Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments
    • D01F9/145Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments from pitch or distillation residues
    • DTEXTILES; PAPER
    • D01NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01FCHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F9/00Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments
    • D01F9/08Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments of inorganic material
    • D01F9/12Carbon filaments; Apparatus specially adapted for the manufacture thereof
    • D01F9/14Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments
    • D01F9/20Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments from polyaddition, polycondensation or polymerisation products
    • D01F9/21Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments from polyaddition, polycondensation or polymerisation products from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D01F9/22Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments from polyaddition, polycondensation or polymerisation products from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds from polyacrylonitriles

Abstract

A graphene enhanced preparation method of a micro-nano film-like carbon fiber is characterized by comprising the following steps: growing graphene by a CVD method by taking metal filament or a hollow metal thin-walled tube as a substrate to serve as a graphene enhanced base material; polymerizing a prepared spinning solution and then uniformly coating the spinning solution on the graphene enhanced base material to form a polymer coating with micro-nano thickness; spinning to form a silk film with micro-nano thickness; performing thermal stabilization and carbonization by an auxiliary heating method of electric induction heating to form a carbon film, and forming a composite micro-nano film-like graphene enhanced carbon fiber by the carbon film and the base material; removing the base material and forming a pure micro-nano film-like graphene enhanced carbon fiber; preparing laminated micro-nano film-like graphene enhanced carbon fibers by repeatedly performing according to the above process method by taking the pure micro-nano film-like carbon fiber as a base material. A micro-nano film-like fiber structure and a preparation method thereof, which are provided by the invention, have the advantages of obviously improving the performance of the carbon fiber, improving the carbon fiber structure, improving production efficiency and reducing manufacturing cost.

Description

A kind of Graphene of the membranaceous carbon fiber of micro-nano strengthens preparation method
Technical field
The present invention relates to Carbon Fiber Technology, the Graphene of the membranaceous carbon fiber of specially a kind of micro-nano strengthens preparation method.
Background technology
Carbon fiber (carbon fiber, abbreviation cf), is a kind of high intensity more than 95% for phosphorus content, high modulus fibre New fiber materials.It is by organic fiber through carbonization and graphitization processing obtain along fiber axial direction pile up micro- Spar ink material.
Carbon fiber has the strong stretching resistance of material with carbon element and the big feature of fiber softening machinability two concurrently, is a kind of mechanics electrical property The excellent new material of energy.The carbon fiber tensile strength of volume production is about 2 to 7gpa at present, and stretch moduluses are about 200 and arrive 700gpa.Close About 1.5 to 2.0 grams of degree is per cubic centimeter, and typically through 3000 DEG C of graphitization processing of high temperature, density is up to 2.0 grams every cube li Rice.Proportion is also lighter than aluminum, and less than the 1/4 of steel, specific strength can reach tens times of iron and steel.Be with highest specific strength and One of specific modulus high-performance fiber.Compared with the metal materials such as titanium, steel, aluminum, carbon fiber has in physical property that intensity is big, mould The features such as amount is high, density is low, linear expansion coefficient is little, is properly termed as the king of new material.Carbon fiber is except having general carbon materials Characteristic outside, its profile has significant anisotropy soft, can be processed into various fabrics.Carbon-fibre reinforced epoxy resin composite wood Material, its specific strength, specific modulus aggregative indicator, are highests in existing sandwich.In not ingress of air and oxidant When, carbon fiber is resistant to more than 3000 degree of high temperature, has prominent heat resistance.In addition carbon fiber also have good resistance to Cryogenic property, such as also not brittle under liquid nitrogen temperature.Carbon fiber all has good corrosion resistant to general organic solvent, acid, alkali Corrosion, insoluble not swollen, corrosion resistance is transcendent, is completely absent the problem got rusty.Carbon fiber also has oil resistant, radioprotective, resists and put Penetrate, absorb the characteristics such as toxic gas and down neutrons.But its resistance to impact is poor, easily damage, under strong acid effect, oxygen occurs Change.
Carbon fiber can be divided into polyacrylonitrile-based carbon fibre, asphalt base carbon fiber, viscose base carbon fibre, phenolic aldehyde by raw material sources Base carbon fibre, gas-phase growth of carbon fibre;Universal, high-strength, middle mold high-strength, high model and superelevation model can be divided into by performance Carbon fiber;It is divided into long filament, chopped fiber and chopped strand by state;It is divided into universal and high-performance type by mechanical property.Universal Carbon fiber strength is 1000 MPas, modulus is about 100g handkerchief.High-performance carbon fibers are divided into high-strength (intensity 2,000,000,000 again Handkerchief, modulus 250g handkerchief) and high model (more than modulus 300g handkerchief).Intensity be more than 4000 MPas be also called superelevation strong type;Modulus Referred to as superelevation model more than 450g handkerchief.What consumption was maximum is polyacrylonitrile pan base carbon fibre.More than 90% carbon fiber on market Based on pan base carbon fibre.
Include fibre with polyacrylonitrile fibre, pitch fibers, viscose or phenolic fibre through the technique that carbonization manufactures carbon fiber The Four processes such as dimension spinning, thermostabilization (pre-oxidation, non-fusible), carbonization, graphitization.
Because the theoretical tensile strength of carbon fiber is up to 180gpa, theoretical modulus be more than 1100gpa it is seen that lifting potentiality Very big.The technical method of raising carbon fiber strength and cost performance mainly has several as follows: (1) first, defect hole is minimum Littleization is to improve the essential measure of carbon fiber strength.(2) precursor High Purity, high strengthening, densification and rounding.(3) pre- It is ensured that on the premise of homogenizing, shortening preoxidation time as far as possible to reduce production cost in oxidizing process.(4) due to high temperature , typically at 1300 to 1800 DEG C, graphitization is typically at 2500 to 3000 DEG C for carbonization temperature.So adopting high temperature of new generation as far as possible Technology, the technology such as microwave, plasma and sensing heating such as carrying out under inert gas shielding, anaerobic state.
But prior art cannot be by carbon fibre precursor, and intermediate and manufactured goods are prepared into micro-nano yardstick, therefore such as Lower four aspects encounter the technology barrier being difficult to overcome:
1st, carbon fibre precursor diameter is difficult to be reduced to below micron and micron, and carbon fiber final products substantially can exist substantial amounts of Defect and hole, defect and hole are the Main Bottlenecks of impact carbon fiber performance again.
Because all there is diffusion in three operation stages such as spinning, thermostabilization (pre-oxidation) and carbonizations and " double diffusion " leading to Road, these passages have finally constituted carbon fiber manufactured goods defect and hole, reduce, reduction defect seeks to make great efforts to reduce " double expansions Dissipate " number of channels, length and size.Calculating shows, the quantity of diffusion admittance and length are highly relevant in film thickness and (are equivalent to The fineness of fiber)Power power,, " fine-denier " is most efficient method.The carbon fiber of maximum intensity in current laboratory (intensity 9g) diameter is 3 μm, the half (respective intensities 7g) of 7 μm of the carbon fiber diameter of only large-scale production.But it is traditional Spining technology be difficult to arrive less than 2 μm filament diameter according to the requirement system of carbon fibre precursor, and meticulous fiber draws to machinery The technique such as stretch and bring very big difficulty." fine-denier " that can not be enough, the minimizing of defect hole reduces and is just difficult to, therefore closely Over year, the raising of carbon fiber strength occurs in that stagnation.
2nd, carbon fibre precursor diameter is difficult to be reduced to below micron and micron, and carbon fiber " skin-core structure " is just difficult to avoid that.
The diffusions in stage such as spinning, thermostabilization (pre-oxidation) and carbonization and when " double diffusion " thermograde be radially by Outer and interior reduction, its densification, vitrification and cyclisation thermal contraction are also from outside to inside, necessarily cause the cortex and loose of densification Core, and need all the time from outside to inside retain diffusion and " double diffusion " passage and cannot close.Carbon fibre precursor diameter is relatively Radially Concentraton gradient changes greatly to also result in greatly diffusate, equally exacerbates the formation of " skin-core structure ".
3rd, carbon fibre precursor diameter is difficult to be reduced to below micron and micron, for making diffusion and " double diffusion " passage be unlikely to Increase and expand, technical process is slowly complicated, lead to technological process long, low production efficiency.
4th, carbon fiber diameter larger it is difficult to using the advanced heating means such as electric induction.The conventional heating methods thermal efficiency is low, work The skill time is long, and material loss is big, causes carbon fiber cost to remain high.
5, if after using the polymer coating of micro-nano thickness being coated on base material and being spun into the cortina of micro-nano thickness Thermostabilization (pre-oxidation, non-fusible and heat treatment), carbonization, graphitization, form the membranaceous carbon fiber of micro-nano, no doubt can realize carbon Fiber " fine-denier ", but the metal on base material can form carbide with carbon fiber in the pyroprocess of technique, causes defect, shadow Ring the raising of carbon fiber performance.
Content of the invention
The purpose of the present invention is for above-mentioned carbon fiber process and fault of construction, provides one kind can improve carbon fiber Can, improve carbon fiber structural, the preparation method of the membranaceous carbon fiber of micro-nano of improve production efficiency and reduction manufacturing cost.
The technical scheme is that a kind of membranaceous carbon fiber of micro-nano Graphene strengthen preparation method it is characterised in that Using filament or hollow metal light-wall pipe for substrate cvd method growth Graphene as Graphene enhancing base materials, the spinning that will prepare Silk stock solution is coated uniformly on, after polymerization, the polymer coating forming micro-nano thickness in above-mentioned Graphene enhancing base materials;Spinning Become the cortina of micro-nano thickness;Then it is allowed to thermostabilization in the way of electrical induction is aided with auxiliary heating and carbonization is formed Carbon film, carbon film forms composite micro-nano membranaceous Graphene enhanced carbon fiber with base material;Base material is removed, forms the membranaceous stone of simple micro-nano Black alkene enhanced carbon fiber;With the membranaceous carbon fiber of above-mentioned simple micro-nano as base material, it is repeated and can make according to above-mentioned process Standby lamination micro-nano membranaceous Graphene enhanced carbon fiber.
Above-mentioned further technical scheme be by simple micro-nano membranaceous Graphene enhanced carbon fiber after carbonization with electric induction plus Heat is aided with the mode graphitization of auxiliary heating, forms the membranaceous Graphene of composite micro-nano with base material and strengthens graphite fibre, by base material Removing, forms the membranaceous Graphene of simple micro-nano and strengthens graphite fibre, strengthens graphite fibre with the membranaceous Graphene of above-mentioned simple micro-nano For base material, repeat according to above-mentioned process, prepare the membranaceous Graphene of lamination micro-nano and strengthen graphite fibre.
Above-mentioned metal substrate material refers to copper, nickel, platinum, silver, iridium, cobalt metal and its alloy.Preferably copper, nickel.
Above-mentioned filament and hollow metal light-wall pipe cyclotomy shape and non-circular.Preferably circular.Wherein, circular diameter For 1 μm~30mm, preferably 3 μm~10 μm and 3mm~10mm.1 μm of non-circular area2~1000mm2, preferably 10 μ m2~100 μm2And 10mm2~100mm2.
Above-mentioned cvd method growth Graphene refers to provide carbon raw material, carbon to filament surface in protective atmosphere at high temperature Raw material cracking the Graphene in 1~10 layer of filament superficial growth.
The carbon film thickness of the membranaceous carbon fiber of above-mentioned simple micro-nano is 1nm~1.5 μm, preferably 10nm~300nm, above-mentioned spinning The thickness of polymer coating is 1~5 times of above-mentioned carbon film thickness.
The spinning solution of above-mentioned preparation can be polyacrylonitrile-radical, asphaltic base, viscose base, phenolic aldehyde base.
Painting method on base material for the above-mentioned spinning solution has dip-coating, spraying.
Above-mentioned spinning adopts dry and wet.
The above-mentioned main electrical induction with the thermostabilization of electrical induction mode, carbonization and graphitization technique is first from relatively Low electromagnetic frequency starts, and extends with technique, progressively adopts high frequency, until radio frequency.Auxiliary mode of heating include electric heating, infrared plus Heat and heating plasma.
Above-mentioned base material removing is at least metal fever and melts removing, metal acid corrosion removing, and electrochemical metal corrosion is de- One of except.Metal acid corrosion removing, in the membranaceous carbon fiber of composite micro-nano and can be combined during electrochemical corrosion removing The membranaceous graphite fibre of micro-nano coats corrosion protective covering.
Further, membranaceous carbon fiber and the membranaceous graphite fibre of micro-nano cvd enhancing can be carried out to above-mentioned micro-nano.Above-mentioned The enhanced carbon source of cvd adopts methane, propylene, propane and acetylene.
The preparation method of the membranaceous carbon fiber of micro-nano of the present invention has as follows a significantly advantage:
1, it is truly realized fiber " fine-denier ", greatly reduce defect and hole, the substantially intensity of lifting carbon fiber and performance.
The present invention coats very thin polymer solution spun (melt) on base material, and thickness is in the micro-nano order of magnitude, minimum Several nanometers can be realized, both achieved fine-denier, can preferably draw stretching fiber again.Because dry spinning has solvent Outwards diffusion process;Wet spinning exist solvent to external diffusion simultaneously coagulator to so-called " double diffusion " process of internal diffusion;Heat All there is diffusion and " double diffusion " process in stabilisation and carbonization, above-mentioned diffusion process is required for diffusion admittance.If diffusion admittance Quantity multiple-length is long, defect hole certainly will be caused not only how not only big but also long, and the intensity of carbon fiber and other performances depend primarily on These defects and hole, the intensity of carbon fiber and performance are just difficult to improve.After the present invention adopts membrane process, film thickness is (quite Fineness in fiber) can reach micro-nano-scale, therefore compared with existing carbon fiber, defect and hole can reduce (reduction) 2 ~3 orders of magnitude.Especially since the presence of base material, cellosilk can bear larger traction tensile force, so that fiber Silk can have good axial preferred orientation.Existed so that filametntary roundness is also guaranteed due to capillary.
2, the cortina of the present invention and carbon film have reached micro-nano-scale, after really realizing fiber " fine-denier ", pre-oxidation, carbon Change and graphited diffusion greatly shortens with " double diffusion " path, the appearance of core loose " skin-core structure " can be avoided.With When, the present invention equal electricity consumption induction heating technique in pre-oxidation, carbonization and graphitization.In pre-oxidation, common technique adopts After mode of heating from outside to inside, fiber pyrocondensation and vitrification form hard crust, defect and hole be big and unrepairable, also The connectivity hole and surface hole defect that have a strong impact on carbon fiber strength and modulus occurs.Because fiber precursor is non-conductor, adopt With electrical induction, heating is heat radially transmission heating cellosilk from inside to outside after first heated substrate, be allowed to vitrification and Densification, radial symmetry gradient is more reasonable, and diffusion admittance can also be repaired.Carbonization early stage fiber or non-conductor, using electricity Sensing heating, after heating remains first heated substrate, heat radially transmits heating cellosilk from inside to outside, is allowed to pyrocondensation, cyclisation And densification, radial symmetry gradient is more reasonable, and " double diffusion " can also repair.
3, the cortina of the present invention and carbon film have reached micro-nano-scale, and diffusion and " double diffusion " time are short, and process is rapid, work Skill complexity substantially reduces, and production efficiency is high.
4, because film thickness only has micro-nano-scale, can be using advanced electrical induction technology, the thermal efficiency is high, technique Time is short, and material loss is little, carbon fiber low cost.
In the pre-oxidation later stage, when carbonization and graphitization, thin film to micro-nano thickness, using sensing heating, microwave with wait The technology such as ion can improve the efficiency of heating surface, shortens heat time heating time, and controls fiber by adjusting heating position and induction frequencies Axially and radially thermograde, realizes pre-oxidation, and carbonization and graphited precise process control.
Particularly,
5, on filament, the graphene layer of growth has intercepted metal and carbon fiber intermediate and manufactured goods, prevents in the middle of carbon fiber Body and manufactured goods generate metal carbides with metal, and cause carbon fiber defect, impact carbon fiber performance.Further, Graphene Provide carbonization, in graphitizing process graphite crystal crystalline growth excellent substrate so that crystalline quality improves, crystallization rate Accelerate.
Meanwhile, this method has the further advantage that
6, lamination can be passed through, membranaceous for micro-nano carbon fiber and the membranaceous graphite fibre of micro-nano are thickened to the thickness needing.
7, after base material removing, the membranaceous carbon fiber of lamination micro-nano and the membranaceous graphite fibre of micro-nano are in hollow form, its specific strength and Specific modulus is higher, and shock resistance shear ability and bending resistance higher.High frequency electric conductivity is more superior simultaneously.
In sum, using the inventive method, the carbon fiber defect producing and hole greatly reduce (reduction), thus at all On improve intensity and the performance of carbon fiber, during heating, radial and axial thermograde is more rationally controlled, and heating means are advanced, The thermal efficiency is high, the process time short (even if being also such by the yardstick that lamination reaches usual carbon fiber).Effectively cut with carbon fiber Area comparison, the tensile strength of carbon fiber reaches as high as more than 40gpa, and, up to 1000gpa, high frequency electric conductivity can be with silver for modulus Quite, while and stating performance in realization, process costs are low.This method has carbon fiber low cost carbonization concurrently and Graphene is high The advantage of performance, the carbon fiber of low-cost and high-performance and its composite can be widely used in space flight, boat as structural material The field such as sky, automobile, high ferro and track traffic, building, can be also used for the electric power such as cable, electric wire, motor, electronics and communication neck Domain.
Specific embodiment
With reference to specific embodiment, the present invention is described in further detail.Without departing from the above-mentioned thought of the present invention In the case of, the various replacements made according to ordinary skill knowledge and customary means or change, it is all contained in model of the present invention In enclosing.
Because traditional spining technology is difficult to infinitely draw and attenuate monofilament, simultaneously meticulous fiber is difficult to apply larger tractive Thus good orientation cannot be obtained, the improved though of the present invention is to coat very thin polymer solution spun on base material to power (melt), thickness, in the micro-nano order of magnitude, preferably 20nm~2 μm scope, had both achieved fine-denier, can preferably draw again Stretching fiber.
The selection of spinning solution and formula are all routine, no newly can be old.Polyacrylonitrile-radical, viscose based sols mainly pass through molten Liquid concentration regulates and controls viscosity, and base material is immersed in Traction after solution melt, and matches with the speed of Traction to obtain To desired thickness of liquid film and orientation, asphaltic base, phenolic aldehyde base melt mainly pass through temperature adjusting viscosity, base material are immersed in molten Traction after liquid melt, and match with the speed of Traction to obtain desired thickness of liquid film and orientation.
Cvd method growth Graphene is conventional method, no newly can be old.
The selection of filament mainly consider whether grow Graphene high-quality substrate and can stringiness.
The shape of base material mainly considers to be easy to traction stretching, and the impact to film forming for the surface tension.Preferably circular fibre Dimension.Cross the active strength that slightly can affect carbon fiber simultaneously, meticulous can increase throwing difficulty and make pull strength too small.It is preferably and justify 3 μm~10 μm and 3mm~10mm of the diameter of shape.
Dip-coating on base material for the spinning solution, spraying is all routine, no newly can be old.
Spinning is conventional dry and wet in addition to no spinning process, no newly can be old.
Thermostabilization technique, carbonization technique and graphitization technique temperature and flow process are all routine, no newly can be old.Mainly with electricity Induction heating mode is carried out.Further, electrical induction, first from the beginning of lower frequency, extends with technique, progressively adopts height Frequently.Auxiliary mode of heating includes electric heating, Infrared Heating and heating plasma.Because film thickness only has micro-nano-scale, adopt The technology such as sensing heating, microwave and plasma can improve the efficiency of heating surface, shortens heat time heating time, and by adjust heating position and Induction frequencies control fiber axial-temperature gradient, realize pre-oxidation, and carbonization and graphited precise process control.
Base material removing is at least metal fever and melts removing, and metal acid corrosion removing, in electrochemical metal corrosion removing One kind.Preferably metal acid corrosion removing.
It is repeated according to above-mentioned process and can prepare the membranaceous carbon fiber of lamination micro-nano and graphite fibre, can reach The thickness needing.
To above-mentioned micro-nano, membranaceous carbon fiber and the membranaceous graphite fibre of micro-nano carry out cvd enhancing, for conventional Enhancement Method, no Newly can be old.
After base material removing, the membranaceous carbon fiber of lamination micro-nano and the membranaceous graphite fibre of micro-nano are in hollow form, its specific strength and ratio Modulus is higher, and anti-shear ability and bending resistance higher.High frequency electric conductivity is superior simultaneously.
The simple membranaceous carbon fiber of micro-nano and simple graphite fibre thin film can use along the axially cutting piece band that formed of fiber.
Specific embodiment be given below:
Embodiment 1
(1) spinning solution is prepared:
Polyacrylonitrile-radical spinning solution: monomers acrylonitrile (an), second comonomer itaconic acid (ita), Third monomer acrylic acid methyl ester. (maa), initiator azodiisobutyronitrile (aibn) becomes terpolymer according to the de- simple form of 96:1:3:0.2 ratio formula post polymerization (pan) solution, then become spinning solution with solvent dimethyl sulfoxide (dmso) according to 1:9 proportions.
(2) cvd method growth Graphene base material: the nickel tinsel of 10 μ m diameter, in hydrogen and nitrogen protection atmosphere, with Methane is carbon raw material, grows 1~10 layer of Graphene with 950~1000 DEG C of growth temperature, increases as Graphene after cooling Strong basis material.
(3) spinning film-forming process: above-mentioned base material contains in the groove of spinning solution through traction immersion, then with 10m/s speed Uniformly pull out, form 0.3~0.5 μm of pan liquid film, be re-introduced into heating chamber by base material electrical induction, being passed through simultaneously Saturated vapor makes solvent volatilization or dissolving volatilization, applies certain drafting force, pan liquid film is frozen into cortina.In said process In, due to heating from-inner-to-outer, solvent evaporation kinetics are pore evaporating principle, and hole from-inner-to-outer subsides, and hole wall melts simultaneously, Implement orientation and degree of crystallinity that steam drafting improves macromolecular chain while densification.
(4) pre-oxidation process: the fiber that gained is covered with pan cortina is introduced in carbide furnace, carries out pre-oxidation treatment, heating Based on electrical induction base material, and it is passed through hot blast, temperature is raised to 240 DEG C from 40 DEG C.Except using electrical induction and will plus The thermal process time foreshortens to outside the 10% of original process time, consistent with conventional method, no newly can be old.
(5) carbonization technique: after pre-oxidation process, logical high pure nitrogen, it is continuously heating to 1500 DEG C, after being down to room temperature, take out fine Dimension, that is, obtain the membranaceous carbon fiber of monolayer micro-nano.Foreshorten to original technique except using electrical induction with by the heating process time Outside the 20% of time, consistent with conventional method, no newly can be old.
(6) cvd repairs and strengthens: membranaceous for above-mentioned monolayer micro-nano carbon fiber is introduced in cvd stove and is carried out for carbon source using propylene Cvd strengthens.
(7) lamination micro-nano membranaceous carbon fiber technique: with the membranaceous carbon fiber of the above-mentioned micro-nano made as base material, according to above-mentioned (3) step of~(6) carries out n time (n=10~100), you can obtain the membranaceous carbon fiber of composite micro-nano of 1~10 μm of thickness.? After fiber outer wall coating plastic protecting film, fiber is immersed the metal that inwall is fallen in electrolytic etching in dilution heat of sulfuric acid, obtains internal diameter For 10 μm, thickness is 1~10 μm of the membranaceous carbon fiber of lamination micro-nano.Calculate by net sectional area, tensile strength is 40gpa, Stretch moduluses are 290gpa.
Embodiment 2
(1) spinning solution is prepared:
Polyacrylonitrile-radical spinning solution: monomers acrylonitrile (an), second comonomer itaconic acid (ita), Third monomer acrylic acid methyl ester. (maa), initiator azodiisobutyronitrile (aibn) becomes terpolymer according to the de- simple form of 96:1:3:0.2 ratio formula post polymerization (pan) solution, then become spinning solution with solvent dimethyl sulfoxide (dmso) according to 1:9 proportions.
(2) cvd method growth Graphene base material: the nickel tinsel of 10 μ m diameter, in hydrogen and nitrogen protection atmosphere, with Methane is carbon raw material, grows 1~10 layer of Graphene with 950~1000 DEG C of growth temperature, increases as Graphene after cooling Strong basis material.
(3) spinning film-forming process: above-mentioned base material contains in the groove of spinning solution through traction immersion, then with 10m/s speed Uniformly pull out, form 0.3~0.5 μm of pan liquid film, be re-introduced into heating chamber by base material electrical induction, being passed through simultaneously Saturated vapor makes solvent volatilization or dissolving volatilization, applies certain drafting force, pan liquid film is frozen into cortina.In said process In, due to heating from-inner-to-outer, solvent evaporation kinetics are pore evaporating principle, and hole from-inner-to-outer subsides, and hole wall melts simultaneously, Implement orientation and degree of crystallinity that steam drafting improves macromolecular chain while densification.
(4) pre-oxidation process: the fiber that gained is covered with pan cortina is introduced in carbide furnace, carries out pre-oxidation treatment, heating Based on electrical induction base material, and it is passed through hot blast, temperature is raised to 240 DEG C from 40 DEG C.Except using electrical induction and will plus The thermal process time foreshortens to outside the 10~30% of original process time, consistent with conventional method, no newly can be old.
(5) carbonization technique: after pre-oxidation process, logical high pure nitrogen, it is continuously heating to 1500 DEG C, after being down to room temperature, take out fine Dimension, that is, obtain the membranaceous carbon fiber of monolayer micro-nano.Foreshorten to original technique except using electrical induction with by the heating process time Outside the 10~20% of time, consistent with conventional method, no newly can be old.
(6) graphitization technique: membranaceous for the micro-nano obtaining carbon fiber is introduced graphitizing furnace, using argon protection, with high-frequency inductor After answering mode to be heated to 3000 DEG C, take out fiber, that is, obtain the membranaceous graphite fibre of monolayer micro-nano.Except being added using electric induction Heat is outer, consistent with conventional method, no newly can be old.
(7) cvd repairs and strengthens: membranaceous for above-mentioned monolayer micro-nano graphite fibre is introduced in cvd stove to enter for carbon source using methane Row cvd strengthens.
(8) lamination micro-nano membranaceous graphite fibre technique: with the membranaceous graphite fibre of the above-mentioned micro-nano made as base material, according to upper The step stating (3)~(7) carries out n time (n=10~100), you can the membranaceous graphite of composite micro-nano obtaining 1~10 μm of thickness is fine Dimension.After fiber outer wall coating plastic protecting film, fiber is immersed the metal that inwall is fallen in electrolytic etching in dilution heat of sulfuric acid, obtains Internal diameter is 30 μm, and thickness is 1~10 μm of the membranaceous graphite fibre of lamination micro-nano.Calculate by net sectional area, tensile strength is 15gpa, stretch moduluses are 900gpa.
Embodiment 3
(1) spinning solution is prepared:
Asphaltic base spinning solution: spinning solution is made by mesophase pitch melt.
(2) cvd method growth Graphene base material: with internal diameter as 3mm, the hollow refine copper pipe of 30 μm of thickness, in hydrogen and 1~10 layer of Graphene in nitrogen protection atmosphere, with methane as carbon raw material, is grown with 950~1000 DEG C of growth temperature, cold But as Graphene enhancing base materials after.
(3) spinning film-forming process: above-mentioned base material is contained in the groove of spinning solution through traction immersion, then with 20m/s speed Degree uniformly pulls out, and forms 0.3~0.5 μm of mesophase pitch liquid film, takes high drafting, and cooled and solidified becomes liquid film in atmosphere Good orientation is obtained while cortina.
(3) curing process: the fiber that gained is covered with Colophonium cortina is introduced in cured furnace, carries out cure treatment, Heating is based on electrical induction base material, and is passed through hot blast, and temperature is raised to 300 DEG C from 40 DEG C.Except using electrical induction and The heating process time is foreshortened to outside the 10% of original process time, consistent with conventional method, no newly can be old.
(4) carbonization technique: after pre-oxidation process, logical high pure nitrogen, it is continuously heating to 1500 DEG C, after being down to room temperature, take out fine Dimension, that is, obtain the membranaceous carbon fiber of monolayer micro-nano.Foreshorten to original technique except using electrical induction with by the heating process time Outside the 20% of time, consistent with conventional method, no newly can be old.
(5) graphitization technique: membranaceous for the micro-nano obtaining carbon fiber is introduced graphitizing furnace, using argon protection, with high frequency After electric induction mode is heated to 3000 DEG C, takes out fiber, that is, obtain the membranaceous graphite fibre of monolayer micro-nano.Except adopting inductance Should heat outer, consistent with conventional method, no newly can be old.
(6) cvd strengthens: membranaceous for above-mentioned monolayer micro-nano graphite fibre is introduced in cvd stove and carries out cvd using propylene for carbon source Strengthen.
(7) lamination micro-nano membranaceous graphite fibre technique: the step according to above-mentioned (1)~(6) carries out n time (n=10~100), Can get the membranaceous graphite fibre of composite micro-nano of 1~10 μm of thickness.After fiber outer wall coating plastic protecting film, by fiber In immersion dilution heat of sulfuric acid, the metal of inwall is fallen in electrolytic etching, and obtaining internal diameter is 3mm, and thickness is 1~10 μm of lamination micro-nano Membranaceous graphite fibre.Calculate by net sectional area, tensile strength is 12gpa, stretch moduluses are 1000gpa.
Embodiment 4
(1) spinning solution is prepared:
Asphaltic base spinning solution: spinning solution is made by mesophase pitch melt.
(2) cvd method growth Graphene base material: with internal diameter as 3mm, the hollow refine copper pipe of 30 μm of thickness, in hydrogen and 1~10 layer of Graphene in nitrogen protection atmosphere, with methane as carbon raw material, is grown with 950~1000 DEG C of growth temperature, cold But as Graphene enhancing base materials after.
(3) spinning film-forming process: above-mentioned base material is contained in the groove of spinning solution through traction immersion, then with 20m/s speed Degree uniformly pulls out, and forms 0.3~0.5 μm of mesophase pitch liquid film, takes high drafting, and cooled and solidified becomes liquid film in atmosphere Good orientation is obtained while cortina.
(3) curing process: the fiber that gained is covered with Colophonium cortina is introduced in cured furnace, carries out cure treatment, Heating is based on electrical induction base material, and is passed through hot blast, and temperature is raised to 300 DEG C from 40 DEG C.Except using electrical induction and The heating process time is foreshortened to outside the 10~30% of original process time, consistent with conventional method, no newly can be old.
(4) carbonization technique: after pre-oxidation process, logical high pure nitrogen, it is continuously heating to 1500 DEG C, after being down to room temperature, take out fine Dimension, that is, obtain the membranaceous carbon fiber of monolayer micro-nano.Foreshorten to original technique except using electrical induction with by the heating process time Outside the 10~20% of time, consistent with conventional method, no newly can be old.
(5) graphitization technique: membranaceous for the micro-nano obtaining carbon fiber is introduced graphitizing furnace, using argon protection, with high frequency After electric induction mode is heated to 3000 DEG C, takes out fiber, that is, obtain the membranaceous graphite fibre of monolayer micro-nano.Except adopting inductance Should heat outer, consistent with conventional method, no newly can be old.
(6) cvd strengthens: membranaceous for above-mentioned monolayer micro-nano graphite fibre is introduced in cvd stove and carries out cvd using propylene for carbon source Strengthen.
(7) lamination micro-nano membranaceous graphite fibre technique: the step according to above-mentioned (1)~(6) carries out n time (n=100), you can Obtain the membranaceous graphite fibre of composite micro-nano of 10 μm of thickness.After fiber outer wall coating plastic protecting film, fiber is immersed dilute sulfur In acid solution, the metal of inwall is fallen in electrolytic etching, and obtaining internal diameter is 3mm, and thickness is that 10 μm of the membranaceous graphite of lamination micro-nano is fine Dimension.Calculate by net sectional area, tensile strength is 12gpa, stretch moduluses are 1000gpa.
(8) axially cutting technique: membranaceous for above-mentioned lamination micro-nano graphite fibre is formed piece band along fiber is axially cutting, obtains Tensile strength is 12gpa, and stretch moduluses are 1000gpa, carry a width of 3 π mm, and thickness is 10 μm of graphite fiber tape.

Claims (12)

1. a kind of Graphene of the membranaceous carbon fiber of micro-nano strengthens preparation method it is characterised in that with filament or hollow metal Light-wall pipe is that substrate cvd method grows Graphene as Graphene enhancing base materials, and the spinning solution that will prepare is uniform after polymerization It is coated in the polymer coating that micro-nano thickness is formed on above-mentioned Graphene enhancing base materials;It is spun to the cortina of micro-nano thickness; Then it is allowed to thermostabilization in the way of electrical induction is aided with auxiliary heating and carbonization forms carbon film, carbon film is formed with base material Composite micro-nano membranaceous Graphene enhanced carbon fiber;Base material is removed, forms simple micro-nano membranaceous Graphene enhanced carbon fiber;More than Stating the membranaceous carbon fiber of simple micro-nano is base material, is repeated according to above-mentioned process and can prepare the membranaceous Graphene of lamination micro-nano Enhanced carbon fiber.
2. a kind of Graphene of the membranaceous carbon fiber of micro-nano according to claim 1 strengthens preparation method it is characterised in that carbon Simple micro-nano membranaceous Graphene enhanced carbon fiber graphitization in the way of electrical induction is aided with auxiliary heating after change, with base material Form the membranaceous Graphene of composite micro-nano and strengthen graphite fibre, base material is removed, form the membranaceous Graphene of simple micro-nano and strengthen graphite Fiber, strengthens graphite fibre as base material with the membranaceous Graphene of above-mentioned simple micro-nano, repeats according to above-mentioned process, preparation The membranaceous Graphene of lamination micro-nano strengthens graphite fibre.
3. a kind of Graphene of the membranaceous carbon fiber of micro-nano according to claim 1 strengthens preparation method it is characterised in that institute State metal substrate material and refer to copper, nickel, platinum, silver, iridium, cobalt metal and its alloy, preferably copper, nickel.
4. a kind of Graphene of the membranaceous carbon fiber of micro-nano according to claim 1 strengthen preparation method it is characterised in that on State filament and hollow metal light-wall pipe cyclotomy shape and non-circular, preferably circular, wherein, circular a diameter of 1 μm~ 30mm, preferably 3 μm~10 μm and 3mm~10mm, 1 μm of non-circular area2~1000mm2, preferably 10 μm2~100 μ m2And 10mm2~100mm2.
5. a kind of Graphene of the membranaceous carbon fiber of micro-nano according to claim 1 strengthens preparation method it is characterised in that institute State cvd method growth Graphene to refer to provide carbon raw material to filament surface in protective atmosphere at high temperature, carbon raw material cracks simultaneously In 1~10 layer of Graphene of filament superficial growth.
6. a kind of Graphene of the membranaceous carbon fiber of micro-nano according to claim 1 strengthen preparation method it is characterised in that on The carbon film thickness stating the membranaceous carbon fiber of simple micro-nano is 1nm~1.5 μm, preferably 10nm~300nm, above-mentioned spinning polymer coating Thickness be 1~5 times of above-mentioned carbon film thickness.
7. a kind of Graphene of the membranaceous carbon fiber of micro-nano according to claim 1 strengthen preparation method it is characterised in that on The spinning solution stating preparation can be polyacrylonitrile-radical, asphaltic base, viscose base, phenolic aldehyde base.
8. a kind of Graphene of the membranaceous carbon fiber of micro-nano according to claim 1 strengthen preparation method it is characterised in that on Stating painting method on base material for the spinning solution has dip-coating, spraying.
9. a kind of Graphene of the membranaceous carbon fiber of micro-nano according to claim 1 strengthen preparation method it is characterised in that on State spinning and adopt dry and wet.
10. a kind of Graphene of the membranaceous carbon fiber of micro-nano according to claim 1 strengthen preparation method it is characterised in that on State the main electrical induction with the thermostabilization of electrical induction mode, carbonization and graphitization technique first from relatively low electromagnetic frequency Start, extend with technique, progressively adopt high frequency, until radio frequency, assist mode of heating to include electric heating, Infrared Heating and plasma Heating.
A kind of Graphene of the membranaceous carbon fiber of 11. micro-nanos according to claim 1 strengthen preparation method it is characterised in that on One of state base material removing and be at least metal fever thawing removing, metal acid corrosion removing, electrochemical metal corrosion removes, Metal acid corrosion removing, can be in the membranaceous carbon fiber of composite micro-nano and the membranaceous graphite of composite micro-nano during electrochemical corrosion removing Fiber coats corrosion protective covering.
A kind of Graphene of the membranaceous carbon fiber of 12. micro-nanos according to claim 1 strengthen preparation method it is characterised in that on State the membranaceous carbon fiber of micro-nano and the membranaceous graphite fibre of micro-nano carry out cvd enhancing, the enhanced carbon source of above-mentioned cvd adopt methane, propylene, Propane and acetylene.
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