CN113817242B

CN113817242B - Conductive flexible material and preparation method and application thereof

Info

Publication number: CN113817242B
Application number: CN202111119088.5A
Authority: CN
Inventors: 刘子瑾
Original assignee: Wuyi University
Current assignee: Wuyi University
Priority date: 2021-09-24
Filing date: 2021-09-24
Publication date: 2023-06-13
Anticipated expiration: 2041-09-24
Also published as: CN113817242A

Abstract

The invention discloses a conductive flexible material, a preparation method and application thereof, wherein the conductive flexible material comprises a styrene-butadiene rubber foam material; the surface of the styrene-butadiene rubber foam material is provided with reduced graphene oxide I; the surface of the reduced graphene oxide I is provided with reduced graphene oxide II and CNT. The GSBR foam material is used as a template, wherein graphene oxide is arranged in the GSBR, and the ordered distribution of the conductive filler in the GSBR composite material is realized by a vacuum auxiliary impregnation method. Compared with random distribution of filler, ordered distribution of filler can construct filler network more efficiently, and conductivity of GSBR composite material is greatly improved under low filler consumption. Meanwhile, anisotropic and isotropic conductive flexible materials are prepared by regulating and controlling the orientation distribution and random distribution of cells of the GSBR foam material.

Description

Conductive flexible material and preparation method and application thereof

Technical Field

The invention relates to the technical field of conductive materials, in particular to a conductive flexible material, a preparation method and application thereof.

Background

Filling a large amount of filler in a polymer matrix to construct a conductive filler network is a main way for greatly improving the conductive performance of a polymer material; however, the addition of a large amount of filler can cause the problems of high cost, difficult processing, reduced mechanical properties and the like of the composite material; the prior art is to assemble nano-fillers into three-dimensional macroscopic structures (porous templates) including graphene aerogel, hexagonal boron nitride (BNNS) aerogel, composite aerogel, etc. in advance, and then fill the polymer is a common method that can effectively form a three-dimensional filler network. But has the problems of poor controllability, low structural strength, high cost and the like of the nano three-dimensional porous template structure, and the problems of low success rate of polymer filling and the like.

Therefore, there is a need to develop a conductive flexible material that has high conductivity.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a conductive flexible material which has high conductivity.

The invention also provides a preparation method of the conductive flexible material.

The invention also provides application of the conductive flexible material.

The first aspect of the present invention provides a conductive flexible material comprising a styrene-butadiene rubber foam material;

the surface of the styrene-butadiene rubber foam material is provided with reduced graphene oxide I;

the surface of the reduced graphene oxide I is provided with reduced graphene oxide II and CNT.

In order to improve the electrical conductivity of polymer materials, it is common practice to fill various fillers with high electrical conductivity, such as carbon fillers and metal powders, in the polymer matrix, to achieve the high electrical conductivity of the composite material at as low a filler content as possible; meanwhile, carbon Nanotubes (CNTs) and reduced graphene oxide (reduced graphene oxide, rGO) are carbon fillers with high conductivity, and the CNTs and the graphene have large specific surface areas, so that the carbon fillers are ideal fillers for improving the conductive performance of the polymer. Filling a large amount of filler in a polymer matrix to construct a conductive filler network is a main way for greatly improving the conductive performance of a polymer material.

Meanwhile, compared with random distribution of the filler in the polymer composite material, regulation and control of ordered distribution of the filler in the polymer composite material are efficient means for constructing a filler network. The realization of ordered distribution of CNTs and graphene in a polymer is an important method for constructing an efficient conductive network with low filler usage.

According to some embodiments of the invention, the number of sheets of reduced graphene oxide I is 2 to 20.

According to some embodiments of the invention, the sheet size of the reduced graphene oxide i is 50nm to 5mm.

According to some embodiments of the invention, the CNT length is 100nm to 10mm.

According to some embodiments of the invention, the number of sheets of the reduced graphene oxide II is 2-20.

According to some embodiments of the invention, the sheet size of the reduced graphene oxide ii is 50nm to 5mm.

According to some embodiments of the invention, the mass fraction of the reduced graphene oxide ii and the CNT in the conductive flexible material is 0.1% to 1%.

According to some embodiments of the invention, the styrene-butadiene rubber foam material comprises the following preparation raw materials: styrene-butadiene rubber emulsion, vulcanizing agent, zinc oxide, accelerator, anti-aging agent, dispersing agent and pH regulator.

According to some embodiments of the invention, the styrene-butadiene rubber emulsion has a solids content of 5% to 50%.

According to some embodiments of the invention, the vulcanizing agent comprises sulfur.

According to some embodiments of the invention, the accelerator comprises at least one of PX (zinc N-ethyl-N-phenyl dithiocarbamate) and ZDC (zinc diethyl dithiocarbamate).

According to some embodiments of the invention, the anti-aging agent comprises anti-aging agent 264 (2, 6-di-tert-butyl-4-methylphenol).

According to some embodiments of the invention, the diffusing agent is NF (sodium methylenedinaphthyl sulfonate).

According to some embodiments of the invention, the pH adjuster is at least one of sodium hydroxide, potassium hydroxide, and cesium hydroxide.

According to some embodiments of the present invention, the styrene-butadiene rubber foam material comprises the following preparation raw materials in parts by weight: 100 parts of styrene-butadiene rubber emulsion, 0.5 to 1.5 parts of vulcanizing agent, 0.5 to 1.5 parts of zinc oxide, 0.5 to 1.5 parts of accelerator, 0.01 to 0.1 part of anti-aging agent, 0.01 to 0.1 part of dispersing agent and 0.01 to 0.1 part of pH regulator.

The second aspect of the present invention provides a method for preparing the above conductive flexible material, comprising the steps of:

S1, preparing a GSBR foam material:

preparing SBR latex (styrene butadiene rubber latex) from preparation raw materials of styrene butadiene rubber foam materials;

adding graphene oxide dispersion liquid I into the SBR latex, reacting at-200 ℃ to-10 ℃, and freeze-drying to obtain a GSBR foam material;

s2, preparing a GSBR/GO-CNT foam material:

mixing graphene oxide dispersion liquid II with the CNT solution to obtain GO-CNT mixed liquid;

adding the GSBR foam material into the GO-CNT mixed liquid for reaction, and drying to obtain a GSBR/GO-CNT foam material;

s3, preparing a conductive flexible material:

and (3) reduction: adding the GSBR/GO-CNT foam material into a reducer solution for reaction, carrying out solid-liquid separation, and collecting a solid phase to prepare the GSBR/rGO-CNT foam material;

vulcanizing: vulcanizing the GSBR/rGO-CNT foam material to obtain the conductive flexible material;

wherein the sequence of the reduction step and the vulcanization step in step S3 is exchangeable.

According to the invention, a GSBR foam material with an open-cell structure is taken as a template, carbon nano-filler composed of Graphene Oxide (GO) and CNT is orderly adsorbed on the inner wall of a three-dimensional communicated cell of the foam material (the orderly adsorption is that the GSBR foam material is taken as the template relative to the unordered distribution of the filler in a matrix, the filler adsorbed on the surface of the GSBR cell realizes the ordered distribution of a three-dimensional space, and the filler in the GSBR is in an unordered distribution state). Then, adopting a reducing agent (hydrazine hydrate) to perform in-situ reduction on the GSBR/GO-CNT foam material (reducing GO into rGO) to obtain the GSBR/rGO-CNT foam material with a filler network. And (3) performing hot press molding on the GSBR/rGO-CNT foam material, wherein the cells are pressed, and filler networks in the cells can be effectively reserved to obtain the conductive flexible material (GSBR composite material) with the filler networks. Compared with the traditional solution blending, emulsion blending and the like, the preparation of the composite material with the three-dimensional filler network by taking the polymer foam material as the template has the characteristics of simplicity, high efficiency and the like, and has wide application prospect.

According to some embodiments of the invention, the mass concentration of the graphene oxide dispersion liquid i in the step S1 is 0.5mg/mL to 3mg/mL.

According to some embodiments of the invention, the mass concentration of the graphene oxide dispersion liquid II in the step S2 is 3 mg/mL-5 mg/mL.

According to some embodiments of the invention, the CNT solution in step S2 has a mass concentration of 0.05mg/mL to 0.2mg/mL.

According to some embodiments of the invention, the volume ratio of the graphene oxide dispersion ii to the CNT solution is 1.5-2.5:1.

According to some embodiments of the invention, the temperature of the reaction in step S2 is 20 ℃ to 30 ℃.

According to some embodiments of the invention, the reducing agent solution in step S3 comprises a hydrazine hydrate solution.

According to some embodiments of the invention, the temperature of the reaction in step S3 is between 90 ℃ and 100 ℃.

According to some embodiments of the invention, the reaction time in step S3 is 3h to 5h.

According to some embodiments of the invention, the temperature of the vulcanization in step S3 is 100 ℃ to 120 ℃.

According to some embodiments of the invention, the vulcanization time in step S3 is t ₉₀ 。

t90 represents a time corresponding to 90% of the degree of vulcanization (change in elastic torque, reflected in the degree of crosslinking of the compound).

The third aspect of the invention provides an application of the conductive flexible material in preparing wearable equipment.

According to the embodiment of the invention, the method has at least the following beneficial effects:

the conductive flexible material takes the foam material as a substrate, and conductive fillers are distributed on the surface of the substrate; has excellent conductivity (conductivity of more than 2.5X10) ^-3 S/cm); meanwhile, the foam material consists of styrene-butadiene rubber and can be bent; has wide application prospect in wearable equipment.

Drawings

FIG. 1 is a schematic illustration of the preparation of GSBR and GSBR/GO foam in an embodiment of the invention;

FIG. 2 is a schematic illustration of the preparation of a GSBR/rGO-CNT composite in accordance with embodiments of the invention;

FIG. 3 is a schematic illustration of the preparation of a foam material by vacuum freezing in an embodiment of the present invention;

FIG. 4 is an SEM image of a cross-section of a GSBR-6.25 foam prepared in example 1 according to the invention (wherein b is an enlarged partial view of a);

FIG. 5 is a cross-sectional SEM image of the AGSBR-50 foam prepared in example 7 and the AGSBR-25 foam prepared in example 8 of the present invention (where a and b are AGSBR-50 foam (b is a partial enlarged view of a); c and d are AGSBR-25 foam (d is a partial enlarged view of c));

FIG. 6 is a cross-sectional SEM image of the AGSBR-12.5 foam prepared in example 9 and the AGSBR-6.25 foam prepared in example 10 of the present invention (where e and f are AGSBR-12.5 foam (b is a partial enlarged view of a); g and h are AGSBR-6.25 foam (d is a partial enlarged view of c));

FIG. 7 is an SEM image of the GSBR-12.5 foam (a) prepared in example 2 and the AGSBR-12.5 foam prepared in example 9 according to the invention;

FIG. 8 is an SEM image of the filler on the inner wall of a conductive flexible material (where a, b and c are GSBR/rGO-CNT-0.36 composite (prepared in example 1), d, e and f are GSBR/rGO-CNT-0.72 composite (prepared in example 5), and g, h and i are GSBR/rGO-CNT-0.92 composite (prepared in example 6));

FIG. 9 is an SEM image of GSBR/rGO-CNT foam material obtained in example 1;

FIG. 10 is an SEM image of an AGSBR/rGO-CNT foam material obtained in example 7;

FIG. 11 is a Raman spectrum of GSBR/rGO-CNT composites (prepared in example 1), GSBR/GO-CNT foams (prepared in example 1) and GSBR/rGO-CNT composites (prepared in example 11);

FIG. 12 is a cross-sectional SEM image of a GSBR/rGO-CNT composite material obtained in example 6 of the present invention;

FIG. 13 is a graph comparing conductivity of GSBR composite (example 12), GSBR/rGO-CNT-0.36 composite (prepared in example 1), GSBR/rGO-CNT-0.72 composite (prepared in example 5) and GSBR/rGO-CNT-0.92 composite (prepared in example 6);

FIG. 14 is a graph comparing conductivity of SBR composite (prepared in example 13), SBR/rGO-CNT-2.1 composite (prepared in example 14), GSBR/rGO-CNT-0.92 composite (prepared in example 6), and AGSBR/rGO-CNT-0.98 composite (prepared in example 7);

FIG. 15 is a graph comparing conductivities (X-axis and Y-axis) of GSBR/rGO-CNT-0.92 composite (prepared in example 6) and AGSBR/rGO-CNT-0.98 composite (prepared in example 7) in different directions.

Detailed Description

The conception and the technical effects produced by the present invention will be clearly and completely described in conjunction with the embodiments below to fully understand the objects, features and effects of the present invention. It is apparent that the described embodiments are only some embodiments of the present invention, but not all embodiments, and that other embodiments obtained by those skilled in the art without inventive effort are within the scope of the present invention based on the embodiments of the present invention.

In the description of the present invention, the descriptions of the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Specific embodiments of the present invention are described in detail below.

Experimental raw materials and reagents selected in the embodiment of the invention are as follows:

carboxylated SBR (styrene butadiene rubber) latex, having a solids content of 50%, manufactured by the company of the morning rubber industry, inc.

Carboxylated multi-walled Carbon Nanotubes (CNT) and Graphene Oxide (GO), purchased from nanjing first-come nanomaterial technologies limited.

Deionized water was produced by a Barnstead Smart 2 pure water purification system (Thermo Scientific).

Sulfur, zinc oxide, NF diffuser (sodium methylene dinaphthyl sulfonate), KOH, accelerator PX (zinc N-ethyl-N-phenyl dithiocarbamate), accelerator ZDC (zinc diethyl dithiocarbamate) and anti-aging agent 264 (2, 6-di-tert-butyl-4-methylphenol) are technical grade adjuvants.

NF dispersing agent (sodium methylene dinaphthyl sulfonate) and KOH are directly added into carboxylated SBR latex under the condition of high-speed stirring, and other auxiliary agents are ground into emulsion by adopting a ball mill for later use.

Vacuum freeze-drying is a simple and effective method for preparing three-dimensional porous materials. In the water dispersion system, water is crystallized into ice crystals at low temperature, other components in the generated ice crystals squeeze other components in the system, the other components are rearranged and assembled, the components are mutually piled to form a three-dimensional structure, and the three-dimensional porous foam material is obtained after ice sublimation. The structure and morphology of the foam material can be controlled by changing the process and composition of the material by vacuum freeze drying.

The GSBR-6.25 foam material with an open pore structure is used as a template, and the GO-CNT is adsorbed on the inner wall of the foam cells by a vacuum auxiliary impregnation method, so that ordered distribution of the filler is realized.

Example 1

The embodiment is a preparation method of a conductive flexible material, which comprises the following steps:

s1, preparing a GSBR foam material (shown in figure 1) by a vacuum freeze drying method:

preparation of SBR latex:

under the condition of high-speed stirring, adding a vulcanization formula (1 part of sulfur, 0.7 part of zinc oxide, 0.35 part of accelerator PX, 0.1 part of accelerator ZDC, 1.0 part of anti-aging agent 264, 0.05 part of NF dispersing agent and 0.05 part of KOH) into 100 parts of carboxylated SBR emulsion; stirring is continued for 2 hours, ultrasonic treatment is carried out for 10 minutes, and the SBR latex added with the vulcanization system is obtained and stirred for standby.

Preparation of GO dispersion:

GO was dispersed in water and stirred for 2 hours and sonicated in an ice-water bath for 10 minutes to give GO dispersion (2 mg/mL).

Preparation of GBRS latex:

diluting the SBR latex added with the vulcanization system by adopting the GO dispersion liquid, preparing SBR with solid content of 6.25% of SBR, and blending the SBR latex with the GO dispersion liquid to prepare GSBR latex (GSBR-6.25).

Placing GSBR in a container, coating an insulating layer on the outside, standing in a freezer at-18 ℃, and freezing overnight (24 h); taking out after complete freezing, rapidly placing in a pre-refrigerated freeze dryer, and freeze drying for 48 hours to obtain GSBR foam material (GSBR-6.25 foam material).

Preparation of S2, GSBR/GO-CNT foam material

Preparation of GO-CNT aqueous dispersion:

GO was dispersed in water with high-speed stirring, and then sonicated in an ice-water bath (about 0 ℃ C.) for 0.5 hours to give GO dispersion (4 mg/mL).

Carboxylated CNTs were dispersed in water with high-speed stirring, and then sonicated in an ice-water bath (about 0 ℃ C.) for 2 hours to obtain a CNT dispersion (0.1 mg/mL).

The aqueous dispersion of CNTs was added to an aqueous solution of GO (GO dispersion: CNT dispersion=2:1 v/v) and the mixed dispersion was stirred for 24 hours to obtain an aqueous GO-CNT dispersion.

Dipping: leaching the GSBR foam material by using GO-CNT aqueous dispersion, soaking the GSBR foam material into the GO-CNT aqueous dispersion with a certain dosage, placing the GSBR foam material into a vacuum oven, defoaming overnight (12 h) at room temperature (about 25 ℃), and then drying in vacuum at 50 ℃; to obtain GSBR/GO-CNT foam material.

Preparation of S3, GSBR/rGO-CNT composite material

And (3) reduction: placing a bracket in a polytetrafluoroethylene liner of a hydrothermal kettle, placing the prepared GSBR/GO-CNT foam material on the bracket, reacting the bracket with hydrazine hydrate aqueous solution under the bracket for 3 hours at 95 ℃, obtaining the GSBR/rGO-CNT foam material after in-situ reduction, filtering, washing with water, and vacuum drying at 60 ℃;

repeating the dipping process in the step S2 and the reduction process in the step S3 to obtain the GSBR/rGO-CNT foam material (GSBR/rGO-CNT-0.36 foam material).

Vulcanizing: hot press vulcanizing the GSBR/rGO-CNT foam material on a plate vulcanizing machine at 110 ℃ for t time ₉₀ To obtain a GSBR/rGO-CNT composite material with orderly distributed filler (GSBR/rGO-CNT-0.36 composite material, wherein 0.36 represents the adsorption quantity of rGO-CNT).

Wherein the adsorption amount of rGO-CNTs in the foam material is calculated by calculating the mass difference before and after the impregnation and reduction treatment (phr is a representation of parts (parts per hundreds of rubber (or resin)) added per 100 parts (by mass) of rubber (or resin)), the adsorption amount of rGO-CNTs is improved by a method of multiple rinsing and impregnation.

Example 2

The difference between this embodiment and embodiment 1 is that the preparation method of the conductive flexible material is:

preparation of GBRS latex in step S1:

diluting the SBR latex added with the vulcanization system by adopting the GO dispersion liquid, preparing SBR with solid content of 12.5% of SBR, and blending the SBR latex with the GO dispersion liquid to prepare GSBR latex (GSBR-12.5).

Example 3

preparation of GBRS latex in step S1:

diluting the SBR latex added with the vulcanization system by adopting the GO dispersion liquid, preparing SBR with solid content of 25% of SBR, and blending the SBR and the GO dispersion liquid to prepare GSBR latex (GSBR-25).

Example 4

preparation of GBRS latex in step S1:

diluting the SBR latex added with the vulcanization system by adopting the GO dispersion liquid, preparing SBR with solid content of 50% of SBR, and blending the SBR and the GO dispersion liquid to prepare GSBR latex (GSBR-50).

Example 5

preparation of S3, GSBR/rGO-CNT composite material

repeating the dipping process in the step S2 and the reduction process in the step S3 to obtain the GSBR/rGO-CNT foam material (GSBR/rGO-CNT-0.72 foam material).

Vulcanizing: GSBR/rGO-CNT foam material on flat plateHot press vulcanization is carried out on a vulcanizing machine, the vulcanization temperature is 110 ℃, and the vulcanization time is t ₉₀ To obtain a GSBR/rGO-CNT composite material with orderly distributed filler (GSBR/rGO-CNT-0.72 composite material, wherein 0.72 represents the adsorption quantity of rGO-CNT).

Example 6

preparation of S3, GSBR/rGO-CNT composite material

repeating the dipping process in the step S2 and the reduction process in the step S3 to obtain the GSBR/rGO-CNT foam material (GSBR/rGO-CNT-0.92 foam material).

Vulcanizing: hot press vulcanizing the GSBR/rGO-CNT foam material on a plate vulcanizing machine at 110 ℃ for t time ₉₀ To obtain a GSBR/rGO-CNT composite material with orderly distributed filler (GSBR/rGO-CNT-0.92 composite material, wherein 0.92 represents the adsorption quantity of rGO-CNT).

Example 7

s1, preparing a GSBR foam material by a vacuum freeze drying method:

preparation of SBR latex:

Preparation of GO dispersion:

Preparation of GBRS latex:

And (3) freezing the GSBR latex from bottom to top by adopting liquid nitrogen, rapidly placing the frozen GSBR latex in a pre-refrigerated freeze dryer, and freeze-drying for 48 hours to obtain the AGSBR foam material (AGSBR-50 foam material).

Preparation of S2, GSBR/GO-CNT foam material

Preparation of GO-CNT aqueous dispersion:

Dipping: leaching the AGSBR foam material by using GO-CNT aqueous dispersion, soaking the AGSBR foam material into a certain amount of GO-CNT aqueous dispersion, placing the AGSBR foam material into a vacuum oven, defoaming overnight (12 h) at room temperature (about 25 ℃), and then drying in vacuum at 50 ℃; obtaining the AGSBR/GO-CNT foam material.

S3, preparation of AGSBR/rGO-CNT composite material

And (3) reduction: placing a bracket in a polytetrafluoroethylene liner of a hydrothermal kettle, placing the prepared AGSBR/GO-CNT foam material on the bracket, reacting the bracket with hydrazine hydrate aqueous solution under the bracket for 3 hours at 95 ℃, obtaining the AGSBR/rGO-CNT foam material after in-situ reduction, filtering, washing with water, and vacuum drying at 60 ℃;

repeating the soaking process in the step S2 and the reducing process in the step S3 to obtain the AGSBR/rGO-CNT foam material (AGSBR/rGO-CNT-0.98 foam material).

Vulcanizing: hot press vulcanizing the AGSBR/rGO-CNT foam material on a flat vulcanizing machine at 110 ℃ for a vulcanizing timeAt t ₉₀ An AGSBR/rGO-CNT composite material with orderly distributed filler (AGSBR/rGO-CNT-0.98 composite material, 0.98 representing the adsorption quantity of rGO-CNT) is obtained.

Example 8

This embodiment is a method for preparing a conductive flexible material, and the difference from embodiment 7 is that:

preparation of GBRS latex in step S1:

diluting the SBR latex added with the vulcanization system by adopting GO dispersion liquid, and preparing SBR with 25 percent of SBR solid content and blending GO to prepare GSBR latex (GSBR-25).

And (3) freezing the GSBR latex from bottom to top by adopting liquid nitrogen, rapidly placing the frozen GSBR latex in a pre-refrigerated freeze dryer, and freeze-drying for 48 hours to obtain the AGSBR foam material (AGSBR-25 foam material).

Example 9

preparation of GBRS latex in step S1:

diluting the SBR latex added with the vulcanization system by adopting GO dispersion liquid, and preparing SBR with 25 percent of SBR solid content and blending GO to prepare GSBR latex (GSBR-12.5).

And (3) freezing the GSBR latex from bottom to top by adopting liquid nitrogen, rapidly placing the frozen GSBR latex in a pre-refrigerated freeze dryer, and freeze-drying for 48 hours to obtain the AGSBR foam material (AGSBR-12.5 foam material).

Example 10

preparation of GBRS latex in step S1:

diluting the SBR latex added with the vulcanization system by adopting GO dispersion liquid, and preparing SBR with solid content of 50% and GO blending to prepare GSBR latex (GSBR-6.25).

And (3) freezing the GSBR latex from bottom to top by adopting liquid nitrogen, rapidly placing the frozen GSBR latex in a pre-refrigerated freeze dryer, and freeze-drying for 48 hours to obtain the AGSBR foam material (AGSBR-6.25 foam material).

Example 11

Preparation of S3, GSBR/rGO-CNT composite material

Vulcanizing: hot press vulcanizing the GSBR/rGO-CNT foam material on a plate vulcanizing machine at 110 ℃ for t time ₉₀ And (3) obtaining the GSBR/GO-CNT composite material with orderly distributed fillers.

And (3) reduction: placing a bracket in a polytetrafluoroethylene liner of a hydrothermal kettle, placing the prepared GSBR/GO-CNT composite material on the bracket, reacting the bracket with hydrazine hydrate aqueous solution under the bracket for 3 hours at 95 ℃, obtaining the GSBR/rGO-CNT composite material after in-situ reduction, filtering, washing with water, and vacuum drying at 60 ℃;

repeating the impregnation process in the step S2 and the vulcanization and reduction process in the step S3 to obtain a GSBR/rGO-CNT composite material (GSBR/rGO-CNT-0.36 composite material, wherein 0.36 represents the adsorption quantity of rGO-CNT).

Example 12

The embodiment is a preparation method of a flexible material, which comprises the following steps:

s1, preparing a GSBR foam material by a vacuum freeze drying method:

preparation of SBR latex:

Preparation of GO dispersion:

Preparation of GBRS latex:

Vulcanizing: hot press vulcanizing the GSBR-6.25 foam material on a flat vulcanizing machine at 110 ℃ for t time ₉₀ And obtaining the GSBR composite material (GSBR-6.25 composite material).

Example 13

s1, preparing an SBR foam material by a vacuum freeze drying method:

preparation of SBR latex:

under the condition of high-speed stirring, adding a vulcanization formula (1 part of sulfur, 0.7 part of zinc oxide, 0.35 part of accelerator PX, 0.1 part of accelerator ZDC, 1.0 part of anti-aging agent 264, 0.05 part of NF dispersing agent and 0.05 part of KOH) into 100 parts of carboxylated SBR emulsion; stirring was continued for 2 hours and sonicated for 10 minutes to give SBR latex (6.25% solids) with added cure system, which was stirred for use.

Placing the SBR latex in a container, coating an insulating layer on the outside, standing in a freezer at-18 ℃, and freezing overnight (24 h); after complete freezing, the mixture was taken out and rapidly placed in a pre-refrigerated freeze dryer and freeze-dried for 48 hours to obtain SBR foam (SBR-6.25 foam).

Vulcanizing: hot press vulcanizing SBR-6.25 foam material in a plate vulcanizing machine at 110 deg.c for t period ₉₀ An SBR composite (SBR-6.25 composite) was obtained.

Example 14

s1, preparing an SBR foam material by an emulsion blending method:

preparation of SBR latex:

under the condition of high-speed stirring, adding a vulcanization formula (1 part of sulfur, 0.7 part of zinc oxide, 0.35 part of accelerator PX, 0.1 part of accelerator ZDC, 1.0 part of anti-aging agent 264, 0.05 part of NF dispersing agent and 0.05 part of KOH) into 100 parts of carboxylated SBR emulsion; stirring is continued for 2 hours, ultrasonic treatment is carried out for 10 minutes, the SBR latex added with a vulcanization system is obtained, and water is added to control the solid content to be 6.25%, so that the SBR-6.25 latex is obtained.

The SBR-6.25 latex was placed in a container and dried to give SBR foam (GSBR-6.25 foam).

Preparation of S2 SBR/GO-CNT foam material

Preparation of GO-CNT aqueous dispersion:

Dipping: leaching the SBR foam material by using GO-CNT aqueous dispersion, soaking the SBR foam material into a certain amount of GO-CNT aqueous dispersion, placing the SBR foam material into a vacuum oven, defoaming overnight (12 h) at room temperature (about 25 ℃), and then vacuum drying at 50 ℃; obtaining the SBR/GO-CNT foam material.

Preparation of S3, GSBR/rGO-CNT composite material

And (3) reduction: placing a bracket in a polytetrafluoroethylene liner of a hydrothermal kettle, placing the prepared SBR/GO-CNT foam material on the bracket, reacting the bracket with hydrazine hydrate aqueous solution under the bracket for 3 hours at 95 ℃, obtaining the SBR/rGO-CNT foam material after in-situ reduction, filtering, washing with water, and vacuum drying at 60 ℃;

repeating the dipping process in the step S2 and the reduction process in the step S3 to obtain the SBR/rGO-CNT foam material (SBR/rGO-CNT-2.1 foam material).

Vulcanizing: hot press vulcanizing SBR/rGO-CNT foam material on a plate vulcanizing machine at 110 ℃ for t time ₉₀ Obtaining the filler withSBR/rGO-CNT composite with order distribution (SBR/rGO-CNT-2.1 composite, 2.1 representing the adsorbed amount of rGO-CNT).

The difference of the freezing process of different GSBR latex is shown in figure 3, and the GSBR foam materials with randomly distributed and oriented foam cells can be prepared respectively by regulating the freezing process of the GSBR latex from figure 3; the GSBR latex is frozen by a refrigerator, and the obtained GSBR foam material has the characteristic of random distribution of cells because the freezing process has no obvious directivity. And performing orientation freezing on the GSBR latex by adopting liquid nitrogen to obtain the GSBR foam material with distributed cell orientation, wherein the GSBR foam material is the AGSBR foam material.

The microscopic morphology of the GSBR foam material in the embodiment of the invention is shown in figures 4 to 10.

As the water content in the system increases, the size of ice crystals formed by water ice formation increases. The growth of ice crystals continuously extrudes the SBR, forming SBR cell walls. When adjacent ice crystals merge with each other, SBR cell walls at the interface are broken to form cells of an open pore structure, and the cells are mutually communicated.

SEM image of a cross-section of a GSBR-6.25 foam prepared according to example 1 of the invention is shown in FIG. 4 (wherein b is an enlarged partial view of a); as shown in FIG. 4a, cells of the GSBR-6.25 foam are oval in shape, the size of the cells is about 120 μm, and adjacent cells are connected to each other. FIG. 4b is an enlarged view of a portion of a GSBR-6.25 foam material, wherein cells are open cell structures as shown by white circles, and the cells are interconnected to form three-dimensionally connected cell channels, thereby providing conditions for the adsorption of GO-CNTs on the inner walls of the cells.

The structures of the AGSBR foam materials prepared in examples 7 to 10 of the present invention are shown in FIGS. 5 to 6.

The SBR latex is diluted by 0, 1, 2 and 4 times respectively by adopting GO dispersion liquid to obtain GSBR latex with solid content of 50%, 25%, 12.5% and 6.25%, the GSBR latex is subjected to freezing treatment from bottom to top by adopting liquid nitrogen, and the AGSBR foam material is prepared after freezing and drying, and the cell structure and the morphology of the AGSBR foam material are different from those of the GSBR foam material, as shown in figures 5-6. Wherein fig. 5b, 5d, 6f and 6h are partial enlarged views of fig. 5a, 5c, 6e and 6g, respectively; meanwhile, the direction indicated by the white arrow is the orientation arrangement direction of the cells.

FIG. 5a is a cross-sectional morphology of an AGSBR-50 foam, the cross-section exhibiting significant orientation structural characteristics; as shown by the white dotted line in FIG. 5b, cells are aligned in the dotted line direction in order, and the size of the cells is about 12. Mu.m.

FIG. 5c shows the cross-sectional morphology of an AGSBR-25 foam, the cross-sectional morphology of the AGSBR-25 foam resembling a terrace, the cells being flat and oriented in the direction indicated by the white arrows in FIG. 5d, the size of the cells being significantly larger, about 50 μm to 100. Mu.m. As shown in FIG. 5d, the cells of the AGSBR-25 foam have an open cell structure, the cells are interconnected in the direction of the white arrow, and the walls of the cells are intact in the direction of the vertical white arrow, forming unidirectional channels of micron size. The number of cells in the AGSBR-25 foam is significantly reduced compared to the number of cells in the AGSBR-50 foam compared to the number of cells per unit area.

FIG. 6e is a cross-sectional morphology of an AGSBR-12.5 foam. Compared with the AGSBR-25 foam material, the size of the foam hole is further increased, and the size of the large hole reaches about 200 mu m; at the same time, the number of cells per unit area is further reduced. Adjacent cells are mutually extruded, and the cells are irregularly shaped. As shown in fig. 6f, cells are connected in the direction of the white arrow, and the walls of the cells have a large number of small pore structures, which may be formed by the combined action of the two stages: in the initial stage, the nucleation rate is larger than the growth rate of ice crystals, a large number of small-size ice crystals are formed, and the ice crystals extrude SBR to form cell walls with small pore structures; in the subsequent stage, the growth rate of the ice crystals is larger than the nucleation rate, the ice crystals grow rapidly along the direction of the temperature gradient, and the ice crystals are contacted, extruded and fused with each other to form large ice crystals, thereby forming a large-sized open-cell structure.

As can be seen from fig. 5 and 6: the purposes of increasing the cell size and connecting cells are achieved by adjusting the freezing process and the solid content of the GSBR latex.

FIG. 6g is a cross-sectional morphology of an AGSBR-6.25 foam with varying cell sizes; the inset of FIG. 6g shows the side morphology of the AGSBR-6.25 foam, and the overall morphology of the AGSBR-6.25 foam can be clearly seen. Wherein the direction indicated by the white arrow is the direction of the orientation distribution of the cells, the red arrow is the side morphology of the AGSBR-6.25 foam material, and the breakage of the cell walls is found.

FIG. 6h shows that AGSBR-6.25 foam is interconnected in the direction of the white arrow; the cell wall surface was rough, which is similar to the morphology of the AGSBR-12.5 foam. Notably, AGSBR-6.25 foam exhibited significant shrinkage in size at the end of freeze-drying when SBR latex was diluted 4 times, which shrinkage could be due to the progressive thinning of foam walls as SBR content was reduced and cell size was increased, with the cell walls providing less support than shrinkage of cells, resulting in deformation or even collapse of cells.

Comparative analysis of GSBR foam and AGSBR foam

During the freezing process, the nucleation rate and growth rate of the ice crystals control the growth and morphology of the ice crystals, thereby affecting the structure and morphology of the three-dimensional porous material. The structure and morphology of GSBR foam material and AGSBR foam material prepared by different freezing processes are observed by adopting SEM.

As shown in fig. 7a, cells in GSBR foam (example 1) had randomly distributed features, with no apparent orientation occurring; fig. 7b is an SEM morphology of AGSBR foam (example 7), with a pronounced orientation structure. This difference results from the difference in the process of preparing GSBR and AGSBR foams. The GSBR foam material is prepared by standing and freezing GSBR latex in a refrigerator; wherein, the latex system is slowly cooled down during the freezing process, and no obvious temperature gradient exists. The AGSBR foam material is prepared by performing orientation freezing treatment on GSBR latex from bottom to top by adopting liquid nitrogen; wherein, the latex system is cooled down faster in the freezing process, and obvious temperature gradient exists in the latex system. For liquid nitrogen oriented frozen GSBR latex, when the growth speed of ice crystals is far higher than the water cooling nucleation speed, the ice crystals grow along the temperature gradient, the ice crystal size becomes large, an orientation distributed ice template is formed, and the AGSBR foam material with orientation distributed cells is obtained. In addition, during the freezing process, the growth and morphology of ice crystals are affected by factors such as the composition and nature of the aqueous dispersion, the material and shape of the container, the pretreatment prior to freezing, and the like.

Microcosmic morphology of GSBR/rGO-CNT foam material

The GSBR-6.5 foam material is used as a template, the GO-CNT is adsorbed on the inner wall of the GSBR-6.5 foam material by adopting vacuum auxiliary impregnation, and then hydrazine hydrate steam is reduced in situ to obtain the GSBR/rGO-CNT-0.36 foam material (example 1), the GSBR/rGO-CNT-0.72 foam material (example 5) and the GSBR/rGO-CNT-0.92 foam material (example 6) are respectively prepared.

FIG. 8 is a cross-sectional morphology of GSBR/rGO-CNT foam. In fig. 8, fig. 8b is a partial enlarged view of fig. 8a, and fig. 8c is a partial enlarged view of fig. 8 b; FIG. 8e is a partial enlarged view of FIG. 8d, and FIG. 8f is a partial enlarged view of FIG. 8 e; fig. 8h is a partial enlarged view of fig. 8g, and fig. 8i is a partial enlarged view of fig. 8 h. By comparing fig. 8a, 8d and 8g, it was found that the rGO-CNT packing adsorbed in the foam material gradually increased by multiple rinsing and impregnation. The analysis was performed as follows:

in the GSBR/rGO-CNT-0.36 foam cell walls shown by the white arrows in fig. 8b adsorb small amounts of filler (fillers), whereas no filler adsorption is found on GSBR cell wall surfaces in the red boxes. This indicates that the filler is only locally adsorbed on the inner wall of the GSBR cells. From fig. 8c it is observed that the filler is tightly adsorbed on the GSBR cell walls.

FIG. 8d shows the SEM morphology of GSBR/rGO-CNT-0.72 foam. Compared with GSBR/rGO-CNT-0.36 foam material, the filler adsorbed by the inner wall of the foam cell is obviously increased. As shown in fig. 8e, a large amount of filler was adsorbed at the place indicated by the white arrow, while the inner wall of GSBR in the red frame was not adsorbed with filler. The adsorption of the filler on the cell inner walls can be clearly observed from fig. 8 f.

FIG. 8g shows the cross-sectional morphology of GSBR/rGO-CNT-0.92 foam. The inner walls of the GSBR foam are substantially filled with the adsorbed filler. No bare inner wall of GSBR was found in fig. 8h, indicating that the filler forms a continuous network of filler on GSBR. Fig. 8i shows that the filler has a pleated structure, tightly adsorbed on the pore walls.

As is known from fig. 8, as the content of filler adsorbed in the GSBR foam material increases, a continuous filler network is gradually formed in the GSBR foam material, providing an advantage for preparing the GSBR composite material having a filler network structure.

Comparative analysis of GSBR/rGO-CNT foam and AGSBR/rGO-CNT foam

The distribution of filler in GSBR/rGO-CNT foam and AGSBR/rGO-CNT foam was analyzed by SEM, and the cross-sectional SEM morphology is shown in FIG. 9. FIG. 9a is a cross-sectional morphology of a GSBR/rGO-CNT foam material, cells are irregularly oval, have a size of about 120 μm, and are interconnected to form three-dimensionally connected cell channels; the cross section of the pore wall is free of filler, and the filler is adsorbed on the inner wall of the cell. FIG. 9b is an enlarged view of a portion of FIG. 9a, black arrows showing a cross-section of the cell walls of the cells, with no filler adsorption on the surfaces; in contrast, a filler (indicated by white arrows) having a wrinkled structure and locally warped was clearly observed on the inner wall of the cells. This indicates that the filler was successfully adsorbed inside the GSBR foam.

FIG. 10c is a cross-sectional morphology of an AGSBR/rGO-CNT foam material with cell sizes between 100 μm and 200 μm and interconnected cells forming cell channels with an oriented structure. In fig. 10d, the black arrows indicate the pore walls of the AGSBR foam, which is smooth in cross section and free of filler adsorption; while the filler was clearly observed on the inner walls of the foam cells (indicated by the white arrows), indicating successful impregnation of the filler into the inner walls of the AGSBR foam. From this it follows that: ordered distribution of filler is achieved in both GSBR and AGSBR foams, notably the distribution of filler is directly related to the structure of communicating cell channels formed in the foam.

Raman spectrum of GSBR/rGO-CNT composite material

The effect of the sequence of reduction and vulcanization on GSBR composites was investigated using raman spectroscopy. FIG. 11 is a Raman spectrum of GSBR/GO-CNT foam and GSBR/rGO-CNT composite. Each composite showed distinct D and G peaks, which correspond to sp, respectively ³ Disordered structural regions and sp of hybridized carbon ² A graphitic structural region of hybridized carbon; intensity ratio I from D peak to G peak _D /I _G The reduction degree of graphene oxide can be analyzed. I of GSBR/GO-CNT composite _D /I _G Is 0.98, 8; reducing to obtain I of GSBR/rGO-CNT composite material _D /I _G 1.20. And the GSBR/rGO-CNT composite material I is obtained by reducing and then vulcanizing the GSBR/GO-CNT foam material _D /I _G 1.26. This shows that both the two processes of vulcanization and reduction and vulcanization can successfully realize the reduction of the GSBR/GO-CNT composite material.

Microcosmic morphology of GSBR/rGO-CNT composite material

The cross-sectional morphology of the GSBR/rGO-CNT-0.92 composite (example 6) was observed by SEM, and the distribution of the filler in the GSBR composite after hot press molding was analyzed, as shown in FIG. 12.

FIG. 12a is a cross-sectional morphology of a GSBR/rGO-CNT-0.92 composite material, wherein the filler is clearly observed in the region indicated by the white arrow, and the filler is orderly arranged at the white dotted line; while the other areas were smoother in surface and no filler was observed. This indicates that the filler is in an ordered distribution in the GSBR/rGO-CNT-0.92 composite. At the same time, the ordered distribution of filler forms a profile with a size similar to the cell size of the GSBR foam. This indicates that cells of the GSBR foam material are pressed during the hot press molding process; and the filler adsorbed in the walls of the foam holes is embedded in the GSBR composite material to form a three-dimensional filler network. Fig. 12b is an enlarged view of a portion of the GSBR composite material, where embedding of the filler in the GSBR composite material is clearly visible at the arrows.

Conductive properties of GSBR/rGO-CNT composites

Four probes are adopted to study the influence of rGO-CNT filler content on the conductivity of the GSBR/rGO-CNT composite material. As shown in FIG. 13, the non-impregnated GSBR foam was hot-pressed to prepare GSBR composites having an electrical conductivity of 1.26X10 ^-7 S/cm. After the GSBR foam material is leached and impregnated, the conductivity of the GSBR/rGO-CNT composite material is gradually improved along with the improvement of the adsorption capacity of the filler. Wherein the electrical conductivity of the GSBR/rGO-CNT-0.36 composite material is 4.56X10 ^- ⁵ S/cm; the electrical conductivity of the GSBR/rGO-CNT-0.92 composite material reaches 2.5X10 ^-3 S/cm。

The reason for this is that the adsorption capacity of the filler on the inner wall of the GSBR foam material is increased, and the filler network formed by the filler in the three-dimensional communicating cell channels of the foam material is continuously perfected. The GSBR/rGO-CNT composite material prepared by hot press molding effectively retains the filler network; the formation of the filler network effectively improves the conductivity of the GSBR/rGO-CNT composite.

The influence of different preparation methods on improving the conductivity of the SBR composite material is studied. The conductivity of the SBR/rGO-CNT prepared by the emulsion blending method (example 14) and the GSBR/rGO-CNT prepared by the template method were compared.

As shown in fig. 14, SBR is an insulating material, and the conductivity of SBR composite material can be greatly improved by adding rGO-CNT. Compared with SBR, the conductivity of the SBR/rGO-CNT-2.1 composite material is improved by 9 orders of magnitude, and reaches 5.26 multiplied by 10 ^-5 S/cm, wherein rGO-CNT is used in an amount of 2.1phr. The electrical conductivity of the GSBR/rGO-CNT-0.92 composite is higher than that of SBR/rGO-CNT-2.1, notably the filler amount (0.92 phr) is lower than that of the SBR/rGO-CNT composite (2.1 phr). The reason is that in the SBR/rGO-CNT composite material prepared by emulsion blending, the filler is randomly distributed, and the ordered distribution of the filler in the SBR composite material can be realized by adopting a template method, so that a filler network can be constructed more efficiently.

In addition, the influence of the structure of the template on the conductivity of the SBR composite material is comparatively studied. Under the condition that the filler dosage is similar, the AGSBR/rGO-CNT-0.98 has higher conductivity, and the conductivity reaches 4.79 multiplied by 10 ^-2 S/cm, conductivity is an order of magnitude higher than that of GSBR/rGO-CNT-0.92. This difference is related to the distribution of filler in the AGSBR/rGO-CNT and GSBR/rGO-CNT composites.

To further investigate the effect of random and oriented cell distribution on the conductivity of the composites, the conductivities of GSBR/rGO-CNT-0.92 and AGSBR/rGO-CNT-0.98 composites in the X and Y axis directions were analyzed, with the X, Y axis representing the direction shown in fig. 15 a. As shown in fig. 15b, for GSBR/rGO-CNT-0.92 composite material, the conductivity in the X-axis direction and the conductivity in the Y-axis direction are substantially the same, exhibiting isotropic properties; whereas for the AGSBR/rGO-CNT-0.98 composite, the conductivity in the Y-axis direction was significantly higher than in the X-axis direction, indicating that it has anisotropic properties. This is consistent with its structural characteristics, and the reason why the conductivity in the Y-axis direction is higher than that in the X-axis direction is probably because the fillers form a tight conductive network in the parallel orientation direction, while the connection between the fillers is smaller in the perpendicular orientation direction than in the former.

In some embodiments of the invention, GSBR foam material with an open-cell structure is used as a template, and the rGO-CNT filler is adsorbed on the inner wall of a GSBR cell by adopting a vacuum-assisted dipping and hydrazine hydrate in-situ reduction method, so that the spatial distribution of the filler in styrene-butadiene rubber is effectively regulated and controlled. After hot press molding, the cells are pressed, and rGO-CNT networks in the foam material can be effectively reserved, so that the GSBR/rGO-CNT composite material with a filler network structure is obtained.

By adopting the template method, the conductive performance of the GSBR composite material is greatly improved under the condition of low filler consumption. Compared with the GSBR composite material without impregnating rGO-CNT, the conductivity of the GSBR/rGO-CNT-0.92 composite material is improved by 4 orders of magnitude compared with the GSBR composite material, and the conductivity reaches 2.5X10 ^-3 S/cm, which is related to the formation of rGO-CNT filler network structure in GSBR/rGO-CNT-0.92 composite.

The electrical conductivity of the composite material can be controlled by changing the cell distribution of the foam material. The GSBR foam material with randomly distributed cells and the AGSBR foam material with distributed cell orientation are successfully prepared by adopting the methods of refrigerator freezing and liquid nitrogen orientation freezing respectively, and the corresponding composite material is prepared by combining the methods of vacuum auxiliary impregnation, hydrazine hydrate in-situ reduction and hot press molding. Wherein the conductivity of the AGSBR/rGO-CNT-0.98 composite material is higher than that of the GSBR/rGO-CNT-0.92 composite material. Meanwhile, the conductivity of the composite material is researched, and the AGSBR/rGO-CNT composite material has the characteristic of anisotropy, while the GSBR/rGO-CNT composite material has the characteristic of isotropy.

And (3) taking the GSBR foam material with an open-cell structure as a template, and orderly adsorbing carbon nanofiller consisting of Graphene Oxide (GO) and CNT on the inner wall of the three-dimensionally communicated cells of the foam material. And then adopting hydrazine hydrate to reflux to perform in-situ reduction on the GSBR/GO-CNT foam material to obtain the GSBR/rGO-CNT foam material with a filler network. And (3) performing hot press molding on the GSBR/rGO-CNT foam material, wherein the cells are pressed, and filler networks in the cells can be effectively reserved to obtain the GSBR composite material with the filler networks. Meanwhile, foam materials with random distribution of cells and orientation distribution of cells are respectively prepared by changing a freezing process, and the influence of the distribution of the cells in the GSBR foam material on the conductivity of the GSBR composite material is researched. Compared with the traditional solution blending, emulsion blending and the like, the preparation of the composite material with the three-dimensional filler network by taking the polymer foam material as the template has the characteristics of simplicity, high efficiency and the like, and has wide application prospect.

In summary, GSBR foam material is used as a template, and ordered distribution of conductive filler in the GSBR composite material is realized by a vacuum auxiliary impregnation method. Compared with random distribution of filler, ordered distribution of filler can construct filler network more efficiently, and can greatly improve conductivity of GSBR composite material under low filler consumption. Meanwhile, anisotropic and isotropic conductive flexible materials are prepared by regulating and controlling the orientation distribution and random distribution of cells of the GSBR foam material.

While the embodiments of the present invention have been described in detail with reference to the specific embodiments, the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art. Furthermore, embodiments of the invention and features of the embodiments may be combined with each other without conflict.

Claims

1. An electrically conductive flexible material characterized by: comprises a styrene-butadiene rubber foam material;

the surface of the reduced graphene oxide I is provided with reduced graphene oxide II and CNT;

the preparation method of the conductive flexible material comprises the following steps:

s1, preparing a GSBR foam material:

preparing SBR latex from preparation raw materials of a styrene-butadiene rubber foam material;

s2, preparing a GSBR/GO-CNT foam material:

S3, preparing a conductive flexible material:

2. A conductive flexible material according to claim 1, wherein: the mass fraction of the total mass of the reduced graphene oxide II and the CNT in the conductive flexible material is 0.1% -1%.

3. A conductive flexible material according to claim 1, wherein: the styrene-butadiene rubber foam material comprises the following preparation raw materials: styrene-butadiene rubber emulsion, vulcanizing agent, zinc oxide, accelerator, anti-aging agent, dispersing agent and pH regulator.

4. A conductive flexible material according to claim 3, wherein: the solid content of the styrene-butadiene rubber emulsion is 5-50%.

5. A conductive flexible material according to claim 3, wherein: the vulcanizing agent comprises sulfur.

6. A conductive flexible material according to claim 3, wherein: the promoter includes at least one of PX and ZDC.

7. A conductive flexible material according to claim 3, wherein: the anti-aging agent comprises 2, 6-di-tert-butyl-4-methylphenol.

8. A conductive flexible material according to claim 3, wherein: the dispersing agent is NF.

9. A conductive flexible material according to claim 3, wherein: the pH regulator is at least one of sodium hydroxide, potassium hydroxide and cesium hydroxide.

10. A conductive flexible material according to claim 1, wherein: the styrene-butadiene rubber foam material comprises the following preparation raw materials in parts by weight: 100 parts of styrene-butadiene rubber emulsion, 0.5 to 1.5 parts of vulcanizing agent, 0.5 to 1.5 parts of zinc oxide, 0.5 to 1.5 parts of accelerator, 0.01 to 0.1 part of anti-aging agent, 0.01 to 0.1 part of dispersing agent and 0.01 to 0.1 part of pH regulator.

11. A conductive flexible material according to claim 1, wherein: the mass concentration of the graphene oxide dispersion liquid I in the step S1 is 0.5 mg/mL-3 mg/mL.

12. A conductive flexible material according to claim 1, wherein: and in the step S2, the mass concentration of the graphene oxide dispersion liquid II is 3 mg/mL-5 mg/mL.

13. A conductive flexible material according to claim 1, wherein: the mass concentration of the CNT solution in the step S2 is 0.05 mg/mL-0.2 mg/mL.

14. A conductive flexible material according to claim 1, wherein: the volume ratio of the graphene oxide dispersion liquid II to the CNT solution is 1.5-2.5:1.

15. A conductive flexible material according to claim 1, wherein: the temperature of the reaction in the step S2 is 20-30 ℃.

16. A conductive flexible material according to claim 1, wherein: the reducing agent solution in step S3 comprises a hydrazine hydrate solution.

17. A conductive flexible material according to claim 1, wherein: the temperature of the reaction in the step S3 is 90-100 ℃.

18. A conductive flexible material according to claim 1, wherein: the reaction time in the step S3 is 3-5 h.

19. A conductive flexible material according to claim 1, wherein: the temperature of the vulcanization in the step S3 is 100-120 ℃.

20. A conductive flexible material according to claim 1, wherein: the vulcanizing time in the step S3 is t ₉₀ 。

21. Use of a conductive flexible material according to any of claims 1 to 3 for the manufacture of a wearable device.