CN113115585A

CN113115585A - Method and equipment for manufacturing carbon nanotube modified fiber reinforced material

Info

Publication number: CN113115585A
Application number: CN201980042079.5A
Authority: CN
Inventors: 孙建旭; 梁嫄; 马豪
Original assignee: Envision Energy Co Ltd
Current assignee: Envision Energy Co Ltd; Envision Energy Ltd
Priority date: 2019-11-13
Filing date: 2019-11-13
Publication date: 2021-07-13
Also published as: WO2021092787A1

Abstract

The invention relates to a method for manufacturing a carbon nanotube modified fiber reinforced material, comprising the following steps: providing a fiber bundle; drawing the fiber bundle; adding carbon nanotubes to a potting tank so that the carbon nanotubes form a potting material with a matrix in the potting tank; soaking the fiber bundle in a traction state into a perfusion material in a glue pouring groove; and extruding the fiber bundle coated with the potting material to form the carbon nanotube-modified fiber reinforcement material. In addition, the invention also relates to equipment for manufacturing the carbon nanotube modified fiber reinforced material. The invention can conveniently introduce the carbon nano tubes into the material and more uniformly distribute the introduced carbon nano tubes among the fiber bundles or the fiber filaments, thereby obviously improving the compression strength of the fiber bundles, reducing the sensitivity of the strength of the material to the manufacturing process and further obviously improving the strength of the material and the blade.

Description

Method and equipment for manufacturing carbon nanotube modified fiber reinforced material

Technical Field

The invention relates to the field of wind power generators in general, and particularly relates to a method for manufacturing a carbon nanotube modified fiber reinforced material. In addition, the invention also relates to equipment for manufacturing the carbon nanotube modified fiber reinforced material.

Background

In recent years, with the increasing environmental importance of various countries, the field of clean energy has been rapidly developing. The clean energy is a novel energy, and has the advantages of wide distribution, reproducibility, small environmental pollution and the like compared with the traditional fossil fuel. Wind power generators are increasingly used as representatives of clean energy.

The blades of the wind driven generator are important components for capturing wind energy, wherein the blades mounted on the hub of the wind driven generator are driven by the wind energy to rotate so as to generate lift force, and the lift force is further converted into torque through a transmission chain in the engine room to drive the generator to generate electricity. In the same case, the larger the impeller formed by the blades, the more wind energy that can be captured, and therefore the longer the blades of the wind turbine, the higher the flapping stiffness of the blades, and the higher the deformation of the blades, so that the more efficient method is needed to increase the flapping stiffness of the blades to avoid the risk of tower-sweeping. Most blades today are constructed from two shells, which are divided into a pressure side shell and a suction side shell. The shell typically has a sandwich panel of glass fiber reinforced plastic and core material and a primary load-bearing component, a spar, wherein the spar contributes about 90% of the overall flapping stiffness.

To improve the strength, especially the flapping stiffness, of the spar, carbon fiber composite materials have been introduced into the spar. Compared with carbon fiber prepreg and carbon fiber fabric infusion, the carbon fiber pultrusion process is increasingly applied to the blade industry due to excellent cost performance, stable process and quality control. Since the compressive strength of carbon fiber composites is much lower than the tensile strength, increasing the compressive strength will facilitate more efficient use of the material. However, the strength of the girder using the carbon fiber is currently sensitive to the manufacturing process, i.e., the girder strength fluctuates in a large range due to the difference or tolerance of the manufacturing process. In view of the trend of the blades to be increasingly longer, the strength of the main beam still needs to be further improved.

Disclosure of Invention

Starting from the prior art, the present invention provides a method and apparatus for manufacturing a carbon nanotube-modified fiber reinforced material (or simply "material"), by which carbon nanotubes can be conveniently introduced into the material and the concentration of the introduced carbon nanotubes in the resin can be ensured and the introduced carbon nanotubes can be more uniformly distributed among fiber bundles or fiber filaments, thereby significantly improving the compressive strength of the fiber-reinforced composite material and reducing the sensitivity of the material strength to the manufacturing process, and further significantly improving the strength of the material and the main force-bearing parts of the blade (such as main beams, etc.).

In a first aspect of the invention, this task is solved by a method for manufacturing a carbon nanotube-modified fibrous reinforcement, comprising the steps of:

providing a fiber bundle;

drawing the fiber bundle;

adding carbon nanotubes to a potting tank so that the carbon nanotubes form a potting material with a matrix in the potting tank;

soaking the fiber bundle in a traction state into a perfusion material in a glue pouring groove; and

the fiber bundle coated with the potting material is extruded to form the carbon nanotube-modified fiber reinforcement.

It should be noted here that in the present invention, the term "fiber bundle" encompasses a single fiber as well as a plurality of bunches of single fibers. And the fiber bundle may comprise one or more fibers.

In one embodiment of the invention, the carbon nanotubes are single-walled carbon nanotubes or multi-walled carbon nanotubes. In addition, the carbon nanotubes may also be present in other forms, such as composites comprising carbon nanotubes, carbon nanotube powder, carbon nanotube particulates, and the like.

In a preferred embodiment of the invention, it is provided that the method further comprises the following steps:

stirring the pouring material in a glue pouring groove.

By this preferred embodiment, the uniformity of the carbon nanotubes in the matrix can be further improved, thereby further improving the compressive strength of the fibers, such as carbon fibers.

In a further preferred embodiment of the invention, it is provided that the volume of the potting compound groove is less than or equal to 100 liters, preferably less than or equal to 50 liters. Through setting up the encapsulating groove that the capacity is less, can improve carbon nanotube's concentration and distribution uniformity to further improve the compressive strength of fibre, like carbon fiber.

In one embodiment of the invention, it is provided that the fiber bundle comprises one or more of the following: carbon fibers, glass fibers, aramid fibers, boron fibers, basalt fibers, and ultra-high modulus polyethylene fibers. Other fiber bundles may be used as desired in other embodiments under the teachings of the present invention.

In a further embodiment of the invention, it is provided that the matrix comprises one or more of the following: thermosetting epoxy resins, vinyl resins, unsaturated polyester resins, phenolic resins, polyurethane resins, and thermoplastic resins. Other substrates may be used as desired in other embodiments, provided that the substrate is capable of being applied to a fiber bundle to form a desired material, under the teachings of the present invention. In a preferred embodiment, the matrix is a resin.

In a further embodiment of the invention, the thermoplastic resin comprises one or more of the following: polypropylene resins, polyethylene resins, polyvinyl chloride resins, polystyrene resins, polyacrylonitrile-butadiene-styrene resins, polyamide resins, polyether ether ketone resins, and polyphenylene sulfide resins. Other resins may be employed as the matrix in other embodiments as desired under the teachings of the present invention.

In a preferred embodiment of the invention, it is provided that the carbon nanotubes are nanomaterials made of carbon nanotubes. The nanomaterial may have a desired shape, such as a sphere, powder, flake, etc. By using nanomaterials with specific shapes made of carbon nanotubes, materials with different physical properties, such as different compressive strengths, can be manufactured.

In a second aspect of the invention, the aforementioned task is solved by an apparatus for manufacturing a carbon nanotube-modified fiber reinforcement, comprising:

a creel having a spool for winding a fiber bundle, wherein the spool is configured to rotate to transport the fiber bundle while the fiber bundle is being pulled;

a pulling device configured to directly or indirectly pull the fiber bundle to bring the fiber bundle into a pulled state;

an injection molding box having a potting tank for containing a potting material and a first adding device for adding carbon nanotubes, wherein the injection molding box is configured to allow a fiber bundle in a pulled state to pass through the potting tank so that the potting material is infiltrated onto the fiber bundle, wherein the potting material comprises a matrix and carbon nanotubes; and

a shaping device configured to compress the fiber bundle infiltrated with the infusion material to form the carbon nanotube-modified fiber reinforcement material.

In a preferred embodiment of the invention, it is provided that the injection-molded case further comprises a second filling device for filling the matrix. With this preferred solution, it is possible to automatically add the matrix dynamically to the injection molding box, thus ensuring sufficient potting material, for example the amount of matrix remaining in the injection molding box can be detected by the level detection means, automatically added below a threshold value, or the matrix can be added in real time according to the matrix consumption rate, thus ensuring the concentration of the introduced carbon nanotubes in the resin. The substrate and the carbon nanotube can be mixed sufficiently by setting a plurality of substrate injection directions to form a vortex during the addition process.

In one embodiment of the invention, it is provided that the device further comprises:

a heater configured to heat the formed carbon nanotube-modified fiber reinforcement material; and/or

A curing chamber configured to cure the heated carbon nanotube-modified fiber reinforcement material.

By means of this embodiment, heating and curing of the material can be achieved, so that a complete automation of the processing is achieved. Furthermore, a cutting device may be provided to cut the material into a desired shape.

In a preferred embodiment of the invention, it is provided that the device further comprises a fiber strand shaping rack which is arranged between the creel and the injection molding box for adjusting the relative position between the fiber strands. By using a shaping frame, the adjustment of the relative position between the fiber bundles can be achieved. For example, the fiber bundles may be evenly spaced apart so that substantially the same resin layer thickness can be filled between the fiber bundles, thereby filling approximately the same carbon nanotubes between them, thereby improving the properties of the material, such as compressive strength.

In a further embodiment of the invention, it is provided that the volume of the potting compound channel is equal to or less than 100 liters, preferably equal to or less than 50 liters. Through setting up the less encapsulating groove of capacity, can improve carbon nanotube's the distribution degree of consistency to further improve the fibre, like the compressive strength of carbon fiber.

In a further preferred embodiment of the invention, it is provided that the injection molding box further has a stirring device, which is configured to distribute the carbon nanotubes uniformly in the matrix. By this preferred embodiment, the uniformity of the carbon nanotubes in the matrix can be further improved, thereby further improving the compressive strength of the fibers, such as carbon fibers.

Furthermore, the invention relates to a carbon nanotube-modified fibrous reinforcement, which is manufactured using the method according to the invention.

In addition, the invention also relates to a main beam for the blade of the wind driven generator, which is provided with the carbon nano tube modified fiber reinforced material.

The invention has at least the following beneficial effects: (1) by adding carbon nanotubes between fiber bundles, especially carbon fiber bundles, the interfacial properties of the fibers and the resin can be remarkably improved, thereby improving the compressive strength of the molded composite material; (2) by dynamically adding carbon nanotubes directly to the potting bath, the concentration and uniform distribution of carbon nanotubes between the fiber bundles can be significantly improved, thereby ensuring uniform and consistent compressive strength, based on the inventors' following insights: the inventor finds that an important reason that the strength of the main beam material is sensitive to the manufacturing process is that the existing stirring process is difficult to uniformly distribute the reinforcing particles in the resin, and the uneven distribution of the reinforcing particles in the resin can cause the strength, especially the compressive strength, of the main beam material to be significantly changed (for example, the strength at a lower concentration of the reinforcing particles is also lower), so that the strength of the main beam material is very dependent on the uniform stirring process of the reinforcing particles; meanwhile, the present inventors have unexpectedly found that, compared to pre-mixing carbon nanotubes and resin in a large container (e.g., 2 ton capacity), dynamically adding carbon nanotubes to a small-capacity potting bath (the capacity of which is generally less than 100L, preferably 50L or less) can ensure the concentration of the introduced carbon nanotubes in the resin and greatly improve the distribution uniformity of the carbon nanotubes in the resin while simplifying the stirring process, because the initial flow rate of the carbon nanotubes is added or the carbon nanotubes are slightly stirred when the carbon nanotubes are dynamically added to the small-capacity potting bath in real time, and the carbon nanotubes can be uniformly distributed by uniformly infiltrating or coating the carbon nanotubes on the fiber bundle without stirring, which can ensure the desired concentration of the carbon nanotubes and improve the stirring uniformity compared to fully stirring in the large container in advance, and the stirring flow is simplified, so that the concentration and uniform distribution of the carbon nano tubes among the fiber bundles can be improved, the compression strength of the fiber bundles is improved, and the sensitivity of the material to the manufacturing process is reduced.

Drawings

The invention is further elucidated with reference to the drawings in conjunction with the detailed description.

FIG. 1 shows a schematic view of an apparatus for manufacturing carbon nanotube-modified fiber reinforcement material according to the present invention;

FIG. 2 shows a cross-sectional view of a carbon nanotube-modified fiber reinforcement material according to the present invention;

FIG. 3 illustrates a cross-sectional view of a spar in accordance with the present invention;

FIG. 4 shows a cross-sectional view of a fan blade according to the present disclosure; and

fig. 5 shows a flow of a method for manufacturing a carbon nanotube-modified fiber reinforcement material according to the present invention.

Detailed Description

It should be noted that the components in the figures may be exaggerated and not necessarily to scale for illustrative purposes. In the figures, identical or functionally identical components are provided with the same reference symbols.

In the present invention, "disposed on …", "disposed over …" and "disposed over …" do not exclude the presence of an intermediate therebetween, unless otherwise specified. Further, "disposed on or above …" merely indicates the relative positional relationship between two components, and may also be converted to "disposed below or below …" and vice versa in certain cases, such as after reversing the product direction.

In the present invention, the embodiments are only intended to illustrate the aspects of the present invention, and should not be construed as limiting.

In the present invention, the terms "a" and "an" do not exclude the presence of a plurality of elements, unless otherwise specified.

It is further noted herein that in embodiments of the present invention, only a portion of the components or assemblies may be shown for clarity and simplicity, but those of ordinary skill in the art will appreciate that, given the teachings of the present invention, required components or assemblies may be added as needed in a particular scenario.

It is also noted herein that, within the scope of the present invention, the terms "same", "equal", and the like do not mean that the two values are absolutely equal, but allow some reasonable error, that is, the terms also encompass "substantially the same", "substantially equal". By analogy, in the present invention, the terms "perpendicular", "parallel" and the like in the directions of the tables also cover the meanings of "substantially perpendicular", "substantially parallel".

The numbering of the steps of the methods of the present invention does not limit the order of execution of the steps of the methods. Unless specifically stated, the method steps may be performed in a different order.

The present invention is based on the following insight of the inventors: one important reason why the strength, especially the compressive strength, of the existing girder materials is sensitive to the manufacturing process is that during the manufacturing process of the existing girder materials, the potting material is stirred in the vat, which results in a distribution of the reinforcing particles in the resin that is very much dependent on the stirring process, and that is not necessarily homogeneously mixed even if mixed for a longer time, thus resulting in a larger variation in the strength of the manufactured material (e.g. lower strength where the concentration of the reinforcing particles is lower), since the amount of reinforcing particles added in the vat is much smaller compared to the amount of resin; the inventors found through research that by dynamically adding carbon nanotubes directly to the potting bath, the concentration and uniform distribution of carbon nanotubes between fiber bundles can be significantly improved, thereby further improving the compressive strength, which is based on the following insight of the inventors; this is because, compared to pre-mixing the carbon nanotubes and the resin in a large container (e.g., 2 tons capacity), dynamically adding the carbon nanotubes directly to a small-capacity potting bath (the capacity of which is generally less than 100L, preferably less than or equal to 50L) can ensure the concentration of the introduced carbon nanotubes in the resin and greatly improve the distribution uniformity of the carbon nanotubes in the resin while simplifying the stirring process, because when the carbon nanotubes are dynamically added to the small-capacity potting bath in real time, a more uniform distribution of the carbon nanotubes can be achieved by adding the initial flow rate of the carbon nanotubes or by slightly stirring, or the carbon nanotubes that are uniformly fed can be uniformly applied to the fiber bundle without stirring, which can improve the stirring uniformity and simplify the stirring process compared to fully stirring in a large container in advance, therefore, the concentration and the uniform distribution of the carbon nano tubes among the fiber bundles can be improved, the compression strength and the material of the fiber bundles are further improved, and the sensitivity of the material to the manufacturing process is reduced.

The invention is further illustrated below with reference to specific embodiments and the accompanying drawings.

Fig. 1 shows a schematic view of an apparatus 100 for manufacturing a carbon nanotube-modified fiber reinforcement material according to the present invention.

As shown in fig. 1, an apparatus 100 for manufacturing a carbon nanotube-modified fiber reinforced material (or simply "material") according to the present invention includes the following components (some of which are optional):

a creel 101 having a spool 102 for winding a fiber bundle. In this embodiment, creel 101 has 12 spools 102, and in other embodiments, other numbers of spools may be provided. The creel 101 may be placed vertically or horizontally and the reel 102 is arranged with its axis of rotation perpendicular to the plane in which the creel 101 lies. The reel 102 is configured to rotate to convey the

fiber bundles

103a, 103b while the

fiber bundles

103a, 103b are pulled. In this embodiment, the spool 102 carries two

different fibre bundles

103a, 103b, in other embodiments more or one fibre bundle may be provided. The

different fiber bundles

103a, 103b may differ, for example, in their composition, thickness, or other parameters. In a preferred embodiment, the

fiber bundles

103a, 103b comprise or are carbon fiber bundles, whereby the tensile strength of the material may be increased.

A pulling device (not shown) configured to directly or indirectly pull the

fiber bundles

103a, 103b to bring the fiber bundles into a pulled state. For example, the pulling device may pull the

fiber bundles

103a, 103b at the finished material 111 or other location. Here, the pulling force may be so great that the

fiber bundles

103a, 103b can be straightened and the reel 102 rotated at a desired speed in order to transport the

fiber bundles

103a, 103b at a desired speed. The pulling device can be, for example, a stepping motor, which pulls and advances the

fiber bundles

103a, 103b by means of a belt.

An optional fiber bundle shaping rack 104 arranged between the creel and the injection molding box for adjusting the relative position between the fiber bundles. By using the shaping frame 104, an adjustment of the relative position between the

fiber bundles

103a, 103b or between the individual fibers of the

fiber bundles

103a, 103b can be achieved. For example, the fiber bundles may be evenly spaced apart so that substantially the same resin layer thickness can be filled between the fiber bundles, thereby filling approximately the same carbon nanotubes between them, thereby improving the properties of the material, such as compressive strength.

An injection molding box 105 having a potting tank (not shown) for containing a potting material and a first adding means for adding carbon nanotubes, wherein the injection molding box is configured to allow the fiber bundle in a pulled state to pass through the potting tank such that the potting material is infiltrated or applied onto the

fiber bundles

103a, 103b, wherein the potting material comprises a resin 106 and carbon nanotubes 107. The carbon nanotubes 107 may be single-walled carbon nanotubes or multi-walled carbon nanotubes. The carbon nanotubes 107 may also be present in other forms, such as composites comprising carbon nanotubes, carbon nanotube powders, carbon nanotube particulates, carbon nanotube nanomaterials, carbon nanotube solutions, and the like. Here, the inventors found through research that reinforcing the fiber bundle with the potting material composed of the resin and the carbon nanotubes can significantly improve the strength, particularly the compressive strength, of the fiber bundle compared to other materials, such as graphene, and the more uniform the distribution of the carbon nanotubes in the resin, the better the strength improvement effect. For this, the carbon nanotubes 107 are dynamically added to the injection molding box 105 by the first adding means, and the resin 106 is dynamically added to the injection molding box 105 by the second adding means. The first and second adding means are for example delivery pipes with electric pumps. By means of the first and second adding means, the numbers 106 and the carbon nanotubes 107 can be automatically added dynamically to the injection molding box 105, thereby ensuring sufficient potting material. The amount of resin remaining in the injection molding box 105 may be detected by a liquid level detection device, the resin may be automatically added when below a threshold value, or the resin may be added in real time according to the resin consumption rate, for example. The resin and the carbon nano tubes can be fully mixed by arranging a plurality of resin conveying pipelines with different input directions in the adding process to enable the output resin to form a vortex. In this embodiment, the

fiber bundles

103a, 103b are passed through the potting bath in the injection molding box 105 at a uniform velocity so that each fiber bundle can be sufficiently coated with a potting material, i.e., a mixture of resin and carbon nanotubes. For example, the carbon nanotubes 107 may be added at a uniform rate (i.e., the same amount of carbon nanotubes 107 may be added per unit time, and the adding rate may be determined according to the desired concentration of the carbon nanotubes 107 in the resin 106), so that the carbon nanotubes 107 input at a uniform rate may be uniformly wetted or coated on the fiber bundle. In this case, the addition position of the carbon nanotubes is preferably close to the position where the fiber bundle contacts the potting material, so that the added carbon nanotubes can be instantly applied to the fiber bundle. The volume of the potting compound channel is equal to or less than 100 liters, preferably equal to or less than 50 liters, for example 40 liters, 30 liters, etc. Through setting up the less encapsulating groove of capacity and dynamic addition carbon nanotube, can improve carbon nanotube's the distribution degree of consistency to further improve the compressive strength of fibre, like carbon fiber. This is because, compared to pre-mixing the carbon nanotubes and the resin in a large container (e.g., 2 tons capacity), dynamically adding the carbon nanotubes directly into a small-capacity potting bath (the capacity of which is generally less than 100L, preferably less than or equal to 50L) will ensure the concentration of the carbon nanotubes in the resin and greatly improve the distribution uniformity of the carbon nanotubes in the resin while simplifying the stirring process, because when the carbon nanotubes are dynamically added into the small-capacity potting bath in real time, a more uniform distribution of the carbon nanotubes can be achieved by adding the initial flow rate of the carbon nanotubes or by slightly stirring, or the carbon nanotubes that are uniformly fed can be uniformly coated on the fiber bundle without stirring, which can ensure the concentration of the carbon nanotubes and improve the stirring uniformity, as well as simplify the stirring process, therefore, the concentration and the uniform distribution of the carbon nano tubes among the fiber bundles can be improved, and the compression strength of the fiber bundles is further improved.

A shaping device 109 configured to press the

fiber bundles

103a, 103b infiltrated or coated with the potting material to form the carbon nanotube-modified fiber reinforcement material 111. The molding device 109 is, for example, a mold.

An optional heater 109 configured to heat the formed carbon nanotube modified fiber reinforcement material 111. By the pressing, the resin 106 and the carbon nanotubes 107 are filled more deeply between the

fiber bundles

103a, 103 b.

An optional curing chamber (not shown) configured to cure the heated carbon nanotube-modified fiber reinforcement material. The curing chamber is optional as curing can also be performed outside the apparatus.

Fig. 2 shows a cross-sectional view of a carbon nanotube modified fiber reinforcement 111 according to the present invention.

As shown in fig. 2, there are two types of

fiber bundles

103a, 103b distributed in the material 111, in other embodiments, fewer or more types of fiber bundles are also contemplated. A mixture of carbon nanotubes 107 and resin 106 is filled between the

fiber bundles

103a, 103b, wherein the carbon nanotubes 107 are uniformly distributed in the mixture. Thus, the material 111 is made with better strength, especially compressive strength, according to the method and apparatus of the present invention.

Fig. 3 shows a cross-sectional view of a main beam 300 according to the present invention.

As shown in fig. 3, the girder 300 comprises upper and lower layers of material 111 according to the invention, and a plurality of layers of compression plates 301 are arranged between the two layers of material 111. Here, the compression plate 301 is laid two layers in the chord direction and four layers in the thickness direction. In other embodiments, other layers of the pressing plates 301 may be laid in the two directions, and other layers of the material 111 may be arranged. As can be seen from fig. 3, by using the material 111 according to the invention, the strength, in particular the compressive strength, of the girder 300 can be increased.

Fig. 4 shows a cross-sectional view of a fan blade 400 according to the invention.

As shown in FIG. 4, the blade 400 includes a leading edge 401 and a trailing edge 405, as well as a pressure side (PS side) 402 and a suction side (SS side) 404. The blade 400 also includes the spar 300 as its primary load-bearing structure, and also includes a web 403 for supporting the spar 300. Here, by using the girder 300 having the material 111, the strength of the girder 300 can be significantly improved, thereby improving the strength of the entire blade 400.

Fig. 5 shows a flow 500 of a method for manufacturing a carbon nanotube-modified fiber reinforcement material according to the present invention.

A fiber bundle is provided at step 502. The fiber bundle may comprise one or more fiber bundles.

At step 504, the fiber bundle is pulled.

At step 506, carbon nanotubes are added to the potting bath such that the carbon nanotubes form a potting material with the matrix in the potting bath. The addition is a field, dynamic addition, thereby increasing the uniformity of the carbon nanotubes in the resin and simplifying the addition and stirring processes. For example, the carbon nanotubes may be added at a uniform rate (i.e., the same amount of carbon nanotubes may be added per unit time, and the rate of addition may be determined according to the desired concentration of carbon nanotubes in the resin), so that the desired concentration of carbon nanotubes is ensured and the carbon nanotubes input at a uniform rate may be uniformly applied to the fiber bundle. In this case, the addition position of the carbon nanotubes is preferably close to the position where the fiber bundle contacts the potting material so that the added material can be instantly applied to the fiber bundle.

At step 508, a potting material is applied to the fiber bundle in a pulled state in a potting bath. For example, the fiber bundle may be pulled through the potting bath such that the potting material in the potting bath is automatically and uniformly applied to the fiber bundle, and in particular to each fiber in the fiber bundle.

At step 510, the fiber bundle coated with the potting material is extruded to form a carbon nanotube-modified fiber reinforcement material.

The invention has at least the following beneficial effects: (1) by adding carbon nanotubes between fiber bundles, especially carbon fiber bundles, the interfacial properties of the fibers and the resin can be remarkably improved, thereby improving the compressive strength of the molded composite material; (2) by dynamically adding carbon nanotubes directly to the potting bath, the concentration and uniform distribution of carbon nanotubes between the fiber bundles can be significantly improved, thereby ensuring uniform and consistent compressive strength, based on the inventors' following insights: the inventor finds that an important reason that the strength of the main beam material is sensitive to the manufacturing process is that the existing stirring process is difficult to uniformly distribute the reinforcing particles in the resin, and the uneven distribution of the reinforcing particles in the resin can cause the strength, especially the compressive strength, of the main beam material to be significantly changed (for example, the strength at a lower concentration of the reinforcing particles is also lower), so that the strength of the main beam material is very dependent on the uniform stirring process of the reinforcing particles; meanwhile, the present inventors have unexpectedly found that, compared to pre-mixing carbon nanotubes and resin in a large container (e.g., 2 ton capacity), dynamically adding carbon nanotubes to a small-capacity potting bath (the capacity of which is generally less than 100L, preferably 50L or less) can ensure the concentration of the introduced carbon nanotubes in the resin and greatly improve the distribution uniformity of the carbon nanotubes in the resin while simplifying the stirring process, because when dynamically adding carbon nanotubes to a small-capacity potting bath in real time, a more uniform distribution of the carbon nanotubes can be achieved by adding the initial flow rate of the carbon nanotubes or slightly stirring and the desired concentration can be ensured, or carbon nanotubes input at a uniform speed can be uniformly coated on a fiber bundle without stirring, compared to fully stirring in a large container in advance, the required concentration of the carbon nano tube can be ensured, the stirring uniformity is improved, the stirring process is simplified, the concentration and the uniform distribution of the carbon nano tube among fiber bundles can be improved, the compression strength of the fiber bundles is improved, and the sensitivity of materials to the manufacturing process is reduced.

Although some embodiments of the present invention have been described herein, those skilled in the art will appreciate that they have been presented by way of example only. Numerous variations, substitutions and modifications will occur to those skilled in the art in light of the teachings of the present invention without departing from the scope thereof. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby.

Claims

A method for manufacturing a carbon nanotube-modified fibrous reinforcement comprising the steps of:

providing a fiber bundle;

drawing the fiber bundle;

adding carbon nanotubes to a potting tank so that the carbon nanotubes form a potting material with a matrix in the potting tank;

soaking the fiber bundle in a traction state into a perfusion material in a glue pouring groove; and

and extruding the fiber bundles soaked with the perfusion material to form the carbon nano tube modified fiber reinforced material.
The method of claim 1, wherein the carbon nanotubes are single-walled carbon nanotubes or multi-walled carbon nanotubes.
The method of claim 1, further comprising the steps of:

stirring the pouring material in a glue pouring groove.
Method according to claim 1, wherein the volume of the glue bath is equal to or less than 100 litres, preferably equal to or less than 50 litres.
The method of claim 1, wherein the fiber bundle comprises one or more of: carbon fibers, glass fibers, aramid fibers, boron fibers, basalt fibers, and ultra-high modulus polyethylene fibers.
The method of claim 1, wherein the substrate comprises one or more of: thermosetting epoxy resins, vinyl resins, unsaturated polyester resins, phenolic resins, polyurethane resins, and thermoplastic resins.
The method of claim 6, wherein the thermoplastic resin comprises one or more of: polypropylene resins, polyethylene resins, polyvinyl chloride resins, polystyrene resins, polyacrylonitrile-butadiene-styrene resins, polyamide resins, polyether ether ketone resins, and polyphenylene sulfide resins.
The method of claim 1, wherein the carbon nanotubes are nanomaterials made of carbon nanotubes.
An apparatus for manufacturing a carbon nanotube-modified fiber reinforcement material, comprising:

a creel having a spool for winding a fiber bundle, wherein the spool is configured to rotate to transport the fiber bundle while the fiber bundle is being pulled;

a pulling device configured to directly or indirectly pull the fiber bundle to bring the fiber bundle into a pulled state;

an injection molding box having a potting tank for containing a potting material and a first adding device for adding carbon nanotubes, wherein the injection molding box is configured to allow a fiber bundle in a pulled state to pass through the potting tank so that the potting material is infiltrated onto the fiber bundle, wherein the potting material comprises a matrix and carbon nanotubes; and

a shaping device configured to compress the fiber bundle infiltrated with the infusion material to form the carbon nanotube-modified fiber reinforcement material.
The apparatus of claim 9, wherein the injection molding cartridge further comprises a second adding device for adding the matrix.
The apparatus of claim 9, further comprising:

a heater configured to heat the formed carbon nanotube-modified fiber reinforcement material; and/or

A curing chamber configured to cure the heated carbon nanotube-modified fiber reinforcement material.
The apparatus of claim 9, further comprising a fiber bundle shaping rack disposed between the creel and the injection molding box for adjusting the relative position between the fiber bundles.
The apparatus according to claim 9, wherein the volume of the glue-pouring trough is equal to or less than 100 liters, preferably equal to or less than 50 liters.
The apparatus of claim 9, wherein the injection molding box further has a stirring device configured to uniformly distribute the carbon nanotubes in the matrix.
Carbon nanotube-modified fibrous reinforcement manufactured using the method according to one of claims 1 to 8.
A spar for a wind turbine blade having the carbon nanotube-modified fiber reinforcement of claim 15.