TWI419919B - Method for making carbon nanotube composite structure - Google Patents

Description

Method for preparing nano carbon tube composite structure

The invention relates to a preparation method of a carbon nanotube composite structure.

The carbon nanotube is a hollow tube rolled from a graphene sheet. Nano carbon tubes have excellent mechanical, thermal and electrical properties and are used in a wide range of applications. For example, carbon nanotubes can be used to make field effect transistors, atomic force microscope tips, field emission electron guns, nano templates, and the like. The application of the carbon nanotubes in the above technology is mainly the application of the carbon nanotubes on the microscopic scale, and the operation is difficult. Therefore, it is of great significance to make the carbon nanotubes have a macroscopic structure and to be applied at a macroscopic level.

In 2002, Jiang Kaili et al. successfully obtained a nanocarbon pipeline from a carbon nanotube array, see "Spinning Continuous Carbon Nanotube Yarns", Nature, V419, P801. The nanocarbon pipeline is composed of a plurality of carbon nanotubes connected end to end and arranged in a preferred orientation along the same direction.

However, the bonding strength between the carbon nanotubes in the nanocarbon pipeline is weak, so the mechanical strength of the nanocarbon pipeline needs to be further improved.

In view of this, it is necessary to provide a preparation method of a carbon nanotube composite structure for preparing good mechanical properties.

A method for preparing a carbon nanotube composite structure, comprising the steps of: dissolving a polymer in an organic solvent to form a polymer solution, the contact angle of the organic solvent to the carbon nanotubes is less than 90 degrees; and A carbon nanotube structure having a self-supporting structure is infiltrated in the polymer solution to composite the polymer with the carbon nanotube structure.

A method for preparing a carbon nanotube composite structure, comprising the steps of: dissolving a polymer monomer in an organic solvent to form a polymer monomer solution, wherein the contact angle of the organic solvent to the carbon nanotube is less than 90 degrees Soaking a self-supporting structure of the carbon nanotube structure in the polymer monomer solution; and polymerizing the polymer monomers in the polymer monomer solution to form a polymer, and forming the same with the nano Carbon tube structure composite.

Compared to the prior art, the carbon nanotube composite structure dissolves the polymer by selecting an organic solvent having a contact angle of less than 90 degrees to the carbon nanotube, so that the polymer can be sufficiently wetted in the nanometer. In the carbon nanotube film structure, it is tightly bonded to the carbon nanotube. Thereby, the carbon nanotube composite structure prepared by the method has excellent mechanical properties.

The invention will be further described in detail below with reference to the accompanying drawings.

A method for preparing a carbon nanotube composite structure according to a first embodiment of the present invention includes the following steps:

S10, dissolving a polymer in an organic solvent to form a polymer solution, the contact angle of the organic solvent to the carbon nanotubes is less than 90 degrees;

S20, impregnating a polymer structure with a self-supporting structure of a carbon nanotube structure to recombine the polymer with the carbon nanotube structure.

In the step S10, the type and nature of the polymer are not limited, and may be selected according to actual needs, and only need to be dissolved in the organic solvent. The polymer may include polyacrylonitrile (PAN), polyvinyl alcohol (PVA), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC). And any one or any combination of polyethylene terephthalate (PET). The degree of polymerization of the polymer can also be selected according to the actual operation. Generally, when the polymer is polyvinyl alcohol, the degree of polymerization of the polyvinyl alcohol is between 1,500 and 3,500. The mass percentage of the polymer in the polymer solution varies depending on the polymer and the organic solvent. Generally, when the polymer is polyvinyl alcohol, the mass percentage of the polyvinyl alcohol in the polyvinyl alcohol solution is approximately between 1% and 9%, so that the polyvinyl alcohol solution is infiltrated in the naphthalene solution. When the carbon nanotube structure is used, the specific surface area of the carbon nanotube structure can be reduced as much as possible.

The organic solvent is used to dissolve the polymer and is capable of infiltrating with the carbon nanotube, thereby enabling the polymer to be sufficiently wetted into the carbon nanotube structure or even infiltrated into the carbon nanotube The inside of the carbon nanotube in the structure can be infiltrated into the hollow portion of the carbon nanotube. Preferably, the organic solvent has a large surface tension while being capable of dissolving the polymer. Specifically, the organic solvent may have a surface tension greater than 20 millinews per meter and a contact angle to the carbon nanotubes of less than 90 degrees. The organic solvent includes Dimethyl Sulphoxide (DMSO), Dimethyl Formamide (DMF), 2,5-dimethyl furan, and N-A. Any one or combination of N-methyl-2-pyrrolidone (NMP). Since the dissolving power of the organic solvent varies depending on the polymer, the selection of the organic solvent is also selected depending on the specific polymer. For example, when the polymer is polyvinyl alcohol, the organic solvent may be selected from dimethyl hydrazine. The surface tension of the dimethyl hydrazine is approximately 43.54 milli-Nilometers per meter and the contact angle to the carbon nanotubes is approximately 70 degrees. The contact angle of the organic solvent to the carbon nanotubes is an angle complementary to the saturation angle of the organic solvent to the carbon nanotubes. The smaller the contact angle of the organic solvent to the carbon nanotubes, the better the wettability of the polymer to the carbon nanotube structure, and the closer the polymer is bonded to the carbon nanotube structure. The greater the surface tension of the organic solvent, the better the wettability of the polymer to the carbon nanotube structure, the stronger the ability to shrink the structure of the carbon nanotube, the polymer and the naphthalene The tighter the carbon nanotube structure is combined.

The carbon nanotube structure is a film-like structure, a linear structure or other three-dimensional structure composed of a plurality of carbon nanotubes. The carbon nanotube structure is a self-supporting structure of a carbon nanotube, and the so-called "self-supporting" means that the carbon nanotube structure does not need to be supported by being disposed on a surface of the substrate, that is, the edge or the opposite end is not supported. The rest of the part can maintain its own specific shape. Since a large number of carbon nanotubes in the self-supporting carbon nanotube structure are attracted to each other by Van der Waals attractive force, the carbon nanotube structure has a specific shape to form a self-supporting structure. . Generally, when the distance between the plurality of carbon nanotubes in the carbon nanotube body is between 0.2 nm and 9 nm, the carbon nanotubes have a large Van der Waals force, thereby The carbon nanotube structure can form the self-supporting structure only by van der Waals force.

The carbon nanotube structure may include at least one carbon nanotube film, and when the carbon nanotube structure comprises a plurality of carbon nanotube films, the plurality of carbon nanotube films are disposed adjacent to each other The carbon tube membranes are combined by van der Waals force.

Referring to FIG. 1 , the carbon nanotube structure film may be a carbon nanotube flocculation film, and the carbon nanotube film is a flocculation treatment of a carbon nanotube raw material, such as a super-aligned array. A self-supporting carbon nanotube structural film is obtained. The carbon nanotube flocculation membrane comprises carbon nanotubes which are intertwined and uniformly distributed. The length of the carbon nanotubes is greater than 10 microns, preferably from 200 microns to 900 microns, such that the carbon nanotubes are intertwined with one another. The carbon nanotubes are attracted to each other by van der Waals forces to form a network structure. Since the large number of carbon nanotubes in the self-supporting carbon nanotube flocculation membrane are mutually attracted and intertwined by van der Waals force, the carbon nanotube flocculation membrane has a specific shape to form a self-supporting structure. . The carbon nanotube flocculation membrane is isotropic. The carbon nanotubes in the carbon nanotube flocculation membrane are uniformly distributed and randomly arranged to form a plurality of gaps or micropores having a size ranging from 1 nm to 500 nm. The area and thickness of the carbon nanotube flocculation membrane are not limited, and the thickness is approximately between 0.5 nm and 100 μm.

The carbon nanotube structure film may be a carbon nanotube rolled film, and the carbon nanotube film is a self-supporting carbon nanotube structure obtained by rolling a carbon nanotube array. membrane. The carbon nanotube rolled film comprises uniformly distributed carbon nanotubes, and the carbon nanotubes are arranged in the same direction or in different directions. The carbon nanotubes in the carbon nanotube rolled film partially overlap each other and are attracted to each other by van der Waals force, and the carbon nanotube structure film has good flexibility and can be bent and folded. In any shape without breaking. Moreover, since the carbon nanotubes in the carbon nanotube rolled film are attracted to each other by the van der Waals force, the carbon nanotube film is a self-supporting structure. The carbon nanotubes in the carbon nanotube rolled film form an angle β with the surface of the growth substrate forming the carbon nanotube array, wherein β is greater than or equal to 0 degrees and less than or equal to 15 degrees, and the angle β is applied The pressure on the carbon nanotube array is related. The larger the pressure, the smaller the angle. Preferably, the carbon nanotubes in the carbon nanotube rolled film are aligned parallel to the growth substrate. The carbon nanotube rolled film is obtained by rolling a carbon nanotube array, and the carbon nanotubes in the carbon nanotube rolled film have different arrangement forms according to the manner of rolling. Specifically, the carbon nanotubes can be arranged in disorder; referring to FIG. 2, when rolling in different directions, the carbon nanotubes are arranged in different directions; when crushed in the same direction, the carbon nanotubes are along a The orientation is preferred and the orientation is preferred. The length of the carbon nanotubes in the carbon nanotube rolled film is greater than 50 microns.

The area of the carbon nanotube rolled film is substantially the same as the size of the carbon nanotube array. The thickness of the carbon nanotube film is related to the height of the carbon nanotube array and the pressure of the rolling, and may be between 0.5 nm and 100 μm. It can be understood that the larger the height of the carbon nanotube array and the lower the pressure applied, the greater the thickness of the prepared carbon nanotube rolled film; on the contrary, the smaller the height of the carbon nanotube array, the more the applied pressure Large, the smaller the thickness of the prepared carbon nanotube rolled film. There is a gap between adjacent carbon nanotubes in the carbon nanotube film, so that a plurality of sizes ranging from 1 nm to 500 nm are formed in the carbon nanotube film. Clearance or micropores.

The carbon nanotube structure film may be a carbon nanotube film. Referring to FIG. 3, the formed carbon nanotube film is a self-supporting structure composed of a plurality of carbon nanotubes. The plurality of carbon nanotubes are arranged in a preferred orientation along the length of the carbon nanotube film. The preferred orientation means that the overall extension direction of most of the carbon nanotubes in the carbon nanotube film is substantially in the same direction. Moreover, the overall extension direction of the majority of the carbon nanotubes is substantially parallel to the surface of the carbon nanotube film. Further, most of the carbon nanotubes in the carbon nanotube film are connected end to end by van der Waals force. Specifically, each of the carbon nanotubes of the majority of the carbon nanotubes extending substantially in the same direction in the carbon nanotube film is connected end to end with the carbon nanotubes adjacent in the extending direction by van der Waals force . Of course, there are a few carbon nanotubes in the carbon nanotube film that deviate from the extending direction. These carbon nanotubes do not constitute an obvious alignment of the majority of the carbon nanotubes in the carbon nanotube film. influences. The self-supporting carbon nanotube film does not need a large-area carrier support, but only provides support force on both sides, and can be suspended in the whole to maintain its own film state, that is, the carbon nanotube film is placed (or When fixed on two supports arranged at a certain distance, the carbon nanotube film located between the two supports can be suspended to maintain its own film state. The self-supporting is mainly achieved by the presence of a continuous carbon nanotube in the carbon nanotube film which is continuously arranged by van der Waals. Specifically, the majority of the carbon nanotubes extending substantially in the same direction in the carbon nanotube film are not absolutely linear and may be appropriately bent; or are not completely aligned in the extending direction, and may be appropriately deviated from the extending direction. . Therefore, it may not be possible to exclude partial contact between the carbon nanotubes juxtaposed in the majority of the carbon nanotubes extending substantially in the same direction.

Specifically, the carbon nanotube film comprises a plurality of continuous and aligned carbon nanotube segments. The plurality of carbon nanotube segments are connected end to end by van der Waals force. Each carbon nanotube segment consists of a plurality of mutually parallel carbon nanotubes. The carbon nanotube segments have any length, thickness, uniformity, and shape. The carbon nanotube film has good light transmittance and the visible light transmittance can reach more than 75%.

When the carbon nanotube structure comprises a multi-layered carbon nanotube film, a preferred angle between the adjacent two layers of carbon nanotube film forming a cross angle α, α is greater than or equal to 0 The degree is less than or equal to 90 degrees (0° ≤ α ≤ 90°). Referring to FIG. 4, preferably, in order to increase the strength of the carbon nanotube film, the intersection angle α is approximately 90 degrees, that is, the arrangement direction of the carbon nanotubes in the adjacent two layers of carbon nanotube film. Basically vertical, forming a cross film. a gap between the plurality of carbon nanotube membranes or between adjacent carbon nanotubes in a carbon nanotube membrane, thereby forming a plurality of uniform distributions in the carbon nanotube structure, Arranged randomly, with a size between 1 nm and 500 nm or micropores.

The carbon nanotube structure can include at least one nanocarbon pipeline structure. When the carbon nanotube structure comprises a plurality of nanocarbon pipeline structures, the plurality of nanocarbon pipeline structures may be disposed in parallel, wound or woven with each other. The nanocarbon pipeline includes at least one nanocarbon pipeline. When the nanocarbon pipeline structure comprises a plurality of nanocarbon pipelines, the nanocarbon pipelines are intertwined or arranged in parallel, and the plurality of nanocarbon pipelines are combined by van der Waals force.

The nano carbon pipeline may be a linear structure formed by processing a carbon nanotube film, and the treatment method of the carbon nanotube membrane comprises a volatile organic solvent infiltration treatment or a mechanical torsion treatment. The volatile organic solvent infiltration treatment may immerse the organic solvent on the surface of the carbon nanotube film by a test tube to infiltrate the entire carbon nanotube film, or the above-mentioned fixed frame formed with the carbon nanotube film may be formed. The whole is immersed in a container containing an organic solvent to infiltrate. The volatile organic solvent is ethanol, methanol, acetone, dichloroethane or chloroform, and ethanol is used in this embodiment. The tension generated by the organic solvent upon volatilization causes the carbon nanotube film to shrink to form the nanocarbon line. Referring to FIG. 5, the nano carbon pipeline obtained by the volatile organic solvent infiltration treatment is a non-twisted nano carbon pipeline, and the non-twisted nano carbon pipeline includes a plurality of nanometers arranged along the length of the nanocarbon pipeline. Carbon tube. Specifically, the non-twisted nanocarbon pipeline includes a plurality of carbon nanotubes connected end to end by van der Waals force and arranged in an axially preferred orientation along the nanocarbon pipeline. The mechanical torsion treatment may be performed by twisting both ends of the carbon nanotube film in the opposite direction by using a mechanical force. Referring to FIG. 6 and FIG. 7 , the nano carbon pipeline obtained by the mechanical torsion treatment is a twisted nano carbon pipeline, and the twisted nano carbon pipeline includes a plurality of nanowires arranged around the nano carbon pipeline. Carbon tube. Specifically, the twisted nanocarbon pipeline includes a plurality of carbon nanotubes connected end to end by van der Waals force and extending helically along the axial direction of the nanocarbon pipeline. It can be understood that the obtained nanocarbon tube can also be obtained by simultaneously or sequentially performing a volatile organic solvent immersion treatment or a mechanical torsion treatment to obtain a twisted nanocarbon line. Please refer to FIG. 8 and FIG. 9 , which are a contraction and twisting one nano carbon pipeline obtained by sequentially performing mechanical torsion treatment and volatile organic solvent infiltration treatment on the carbon nanotube film.

After the polymer is infiltrated into the carbon nanotube structure, it is combined with the carbon nanotube to form the carbon nanotube composite structure. Since the contact angle of the organic solvent to the carbon nanotubes is less than 90 degrees, the polymer dissolved in the organic solvent can be infiltrated together with the organic solvent in the carbon nanotube structure and the carbon nanotubes are tight. The combination is combined to obtain a carbon nanotube composite structure having excellent mechanical properties.

The method for preparing the carbon nanotube composite structure may further comprise the following steps: S30, drying the polymer-infiltrated carbon nanotube structure.

In step S30, the organic solvent in the polymer-impregnated carbon nanotube structure is removed, thereby obtaining the organic solvent-free carbon nanotube composite structure. At this time, the mass percentage of the polymer in the carbon nanotube composite structure is approximately between 2.5% and 21.5%. The manner of drying the polymer-impregnated carbon nanotube structure is not limited, and it may be carried out by natural air drying or by heater drying without merely oxidizing the polymer.

A method for preparing a carbon nanotube composite structure according to a second embodiment of the present invention includes the following steps:

S110, a polymer monomer is dissolved in an organic solvent to form a polymer monomer solution, the contact angle of the organic solvent to the carbon nanotubes is less than 90 degrees;

S120, infiltrating a self-supporting structure of a nanocarbon pipeline structure in the polymer monomer solution;

S130, polymerizing the polymer monomers in the polymer monomer solution to form a polymer and compounding with the nanocarbon pipeline structure.

In step S110, the polymer monomer includes any one or a combination of acrylonitrile, vinyl alcohol, propylene, styrene, vinyl chloride or ethylene terephthalate.

The preparation method of the carbon nanotube composite structure provided by the embodiment of the present invention is basically similar to the steps and principles of the preparation method of the nano carbon tube composite structure provided by the first embodiment of the present invention, and the main difference is that the polymer is made The in-situ polymerization is carried out when the carbon nanotube structure is infiltrated, that is, the functions completed by the S20 step in the first embodiment of the present invention are completed through two steps of steps S120 and S130. The solubility of the polymer monomer is greater than the solubility of the polymer formed by polymerization of the polymer monomer in the same organic solvent. Therefore, it is possible to select a polymer having poor solubility in the organic solvent to be combined with the carbon nanotube structure, and only the corresponding polymer monomer may have a good solubility in the organic solvent. It is possible to make the selection of the polymer wider, that is, to enable the carbon nanotube film structure to be infiltrated with a polymer which is insoluble in the organic solvent.

In order to more clearly illustrate the preparation method of the carbon nanotube composite structure of the present invention, the following description will be given by way of specific examples. For the structure of the carbon nanotube film, the wire or other shapes, the treatment methods are relatively similar. Therefore, the specific embodiment is described by taking the twisted nanocarbon pipeline in the nano carbon pipeline as an example.

First, polyvinyl alcohol was dissolved in dimethyl hydrazine to prepare a polyvinyl alcohol solution. The degree of polymerization of the polyvinyl alcohol is between 1750 and 3300. The contact angle of the dimethyl hydrazine to the carbon nanotubes is approximately 70 degrees, and the surface tension of the dimethyl hydrazine is approximately 43.45 milli-Nilometers per meter. The mass percentage of the polyvinyl alcohol in the polyvinyl alcohol solution or the concentration of the polyvinyl alcohol solution is approximately between 1% and 9%. Preferably, the mass percentage of the polyvinyl alcohol in the polyvinyl alcohol solution is approximately 5%, so that the polyvinyl alcohol can fill the twisted nano carbon pipeline and can utilize its surface tension to pull The distance between the carbon nanotubes in the near-nano carbon pipeline, thereby reducing the diameter of the twisted nanocarbon pipeline as much as possible, and obtaining a nanocarbon pipeline having a large strength.

Next, the twisted nanocarbon line in FIG. 6 is impregnated into the polyvinyl alcohol solution to wet the polyvinyl alcohol and the twisted nanocarbon line to form as shown in FIGS. 10 and 11 One of the carbon nanotube composite lines.

Comparing Fig. 6, Fig. 8 and Fig. 10, and Fig. 7, Fig. 9 and Fig. 11, the carbon nanotube composite line is based on the same twisted carbon nanotube line and the contracted and twisted nano carbon line. Nano carbon tube structure, but after treatment, the diameter and density are not the same. The carbon nanotube composite wire has a smaller diameter relative to the twisted nanocarbon pipeline, and the density becomes larger, and the gap between the carbon nanotubes is substantially filled with polyvinyl alcohol. Referring to FIG. 12, the diameters of the twisted nanocarbon pipeline of FIG. 6, the contracted and twisted nanocarbon pipeline of FIG. 8, and the nanocarbon tube composite line of FIG. 10 are respectively obtained, and the axial direction resistance is obtained. Tensile strength and Tensile load. It can be seen from the figure that the tensile strength and tensile load of the twisted carbon nanotubes are significantly improved after composite formation of the carbon nanotube composite wire. Further, please refer to FIG. 13 , which is a tensile-strain comparison diagram of the twisted nanocarbon pipeline of FIG. 6 , the contracted and twisted nanocarbon pipeline of FIG. 8 , and the carbon nanotube composite wire of FIG. 10 . It can be seen from the figure that after the twisted carbon nanotubes are composited to form a carbon nanotube composite wire, under the same strain, the tensile strength of the carbon nanotube composite wire is greater than that of the twisted nanocarbon pipeline. And the tensile strength of the contracted and twisted nanocarbon line. Therefore, it can be explained that the carbon nanotube composite structure having a large tensile strength, a large tensile load, and a large tensile strength/strain ratio can be obtained by the preparation method of the carbon nanotube structure.

Please refer to FIG. 14 , which is a comparison diagram of the tensile strength obtained when the carbon nanotube composite wire is formed in different concentrations of polyvinyl alcohol solution. As can be seen from the figure, the tensile strength of the carbon nanotube composite wire is related to the concentration of the polyvinyl alcohol solution, and the mass percentage of the polyvinyl alcohol in the polyvinyl alcohol solution is approximately 5 When the concentration of % or the polyvinyl alcohol solution is approximately 5%, the nano carbon tube composite wire has the highest tensile strength and can reach 2 GPa. However, at that concentration, the tensile strength of the carbon nanotube composite wire is greater than 1.2 GPa.

Please refer to FIG. 15 , which is a comparison of tensile load and diameter obtained when the carbon nanotube composite wire is formed in different concentrations of polyvinyl alcohol solution. As can be seen from the figure, when the concentration of the polymer is approximately 5%, the diameter of the carbon nanotube composite wire is the smallest and the tensile load is the largest. Please refer to FIG. 16 , which is a comparison diagram of the tensile strength and diameter of the carbon nanotube composite wire formed by the polyvinyl alcohol solution at different temperatures. It can be seen from the figure that although the diameter of the carbon nanotube composite wire increases with the increase of temperature, the tensile strength decreases, but the tensile strength changes less than 50 degrees, and has a good temperature. stability. And because of the lower temperature required in the production department, it is advantageous for mass production.

Figure 17 is a graph showing the tensile strength of carbon nanotube composite wires composed of 425 micrometers and 250 micrometers of carbon nanotubes at different diameters. As can be seen from the figure, the carbon nanotube composite wire composed of carbon nanotubes of different lengths has a tensile strength of more than 1.5 GPa at a diameter of 4 to 24 micrometers, and has excellent mechanical properties.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by those skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

no:

Figure 1 is a scanning electron micrograph of a carbon nanotube film.

Figure 2 is a scanning electron micrograph of a carbon nanotube rolled film.

Figure 3 is a scanning electron micrograph of a carbon nanotube film.

Figure 4 is a scanning electron micrograph of a carbon nanotube cross film.

Figure 5 is a scanning electron micrograph of a non-twisted nanocarbon pipeline.

Figure 6 is a scanning electron micrograph of a twisted nanocarbon line.

Figure 7 is an enlarged scanning electron micrograph of the twisted nanocarbon line of Figure 6.

Figure 8 is a scanning electron micrograph of a contracted and twisted nanocarbon line.

Figure 9 is an enlarged scanning electron micrograph of the contracted and twisted nanocarbon line of Figure 8.

FIG. 10 is a scanning electron micrograph of a carbon nanotube composite wire prepared by a method for preparing a carbon nanotube structure according to an embodiment of the present invention.

Figure 11 is an enlarged scanning electron micrograph of the carbon nanotube composite wire of Figure 10.

Figure 12 is a bar graph of the diameter, tensile load and tensile strength of the twisted nanocarbon line of Figure 6, the contracted and twisted nanocarbon line of Figure 8, and the carbon nanotube composite line of Figure 10. .

Figure 13 is a tensile-strain comparison of the twisted nanocarbon line of Figure 6, the shrinkage and twisted nanocarbon line of Figure 8, and the carbon nanotube composite line of Figure 10.

Figure 14 is a graph showing the tensile strength of the carbon nanotube composite wire of Figure 10 when formed in different concentrations of polyvinyl alcohol solution.

Figure 15 is a graph showing the tensile load and diameter of a mixture of different concentrations of polyvinyl alcohol in the carbon nanotube composite wire of Figure 10.

Figure 16 is a graph showing the tensile strength and diameter of a polyvinyl alcohol solution at different temperatures in the carbon nanotube composite wire of Figure 10.

Figure 17 is a graph showing the tensile strength of carbon nanotube composite wires composed of 425 micrometers and 250 micrometers of carbon nanotubes at different diameters.

Claims (13)

A method for preparing a carbon nanotube composite structure, comprising the following steps:
Dissolving a polymer in an organic solvent to form a polymer solution having a contact angle of less than 90 degrees to the carbon nanotubes; and impregnating a polymer structure of the self-supporting structure of the carbon nanotube film with the polymer A solution that recombines the polymer with the carbon nanotube membrane structure. The method for preparing a carbon nanotube composite structure according to claim 1, wherein the organic solvent has a contact angle of 70 degrees or less with respect to the carbon nanotube. The method for preparing a carbon nanotube composite structure according to claim 1, wherein the organic solvent has a surface tension of 20 mN/m or more. The method for preparing a carbon nanotube composite structure according to claim 3, wherein the organic solvent has a surface tension of 40 mN/m or more. The method for preparing a carbon nanotube composite structure according to claim 1, wherein the organic solvent comprises any one of dimethyl hydrazine, dimethylformamide and N-methylpyrrolidone or combination. The method for preparing a carbon nanotube composite structure according to claim 1, wherein the polymer comprises polyacrylonitrile, polyvinyl alcohol, polypropylene, polystyrene, polyvinyl chloride and polyparaphenylene. Any one or combination of ethylene formate. The method for preparing a carbon nanotube composite structure according to claim 1, wherein the polymer solution comprises polyvinyl alcohol and dimethyl fluorene, and the polyvinyl alcohol is in the polymer solution. The mass percentage is between 1% and 9%. The method for preparing a carbon nanotube composite structure according to claim 7, wherein the polyvinyl alcohol has a polymerization degree of between 1750 and 3300. The method for preparing a carbon nanotube composite structure according to claim 1, wherein the carbon nanotube membrane structure comprises a carbon nanotube flocculation membrane, a carbon nanotube membrane, or at least Two layers of carbon nanotube film. The method for preparing a carbon nanotube composite structure according to claim 9, wherein the carbon nanotube membrane structure comprises a plurality of carbon nanotubes connected by van der Waals, the plurality of nanoparticles The carbon tube is substantially parallel to a surface of the carbon nanotube membrane structure. The method for preparing a carbon nanotube composite structure according to claim 1, wherein the method further comprises the following steps:
The polymer impregnated carbon nanotube structure is dried. The method for preparing a carbon nanotube composite structure according to claim 11, wherein the mass percentage of the polymer in the carbon nanotube composite structure is between 2.5% and 21.5%. A method for preparing a carbon nanotube composite structure, comprising the following steps:
Dissolving a polymer monomer in an organic solvent to form a polymer monomer solution, the organic solvent having a contact angle to the carbon nanotubes of less than 90 degrees;
Soaking a self-supporting structure of the carbon nanotube film structure to the polymer monomer solution; and polymerizing the polymer monomers in the polymer monomer solution to form a polymer, and forming the same with the nano Carbon tube membrane structure composite.