High-conductivity graphene-based fabric and preparation method thereof

Abstract

The invention relates to a high-conductivity graphene-based fabric and a preparation method thereof. The conductive fabric has a microstructure that polymer fibers are wrapped by graphene sheet layers, when the conductive fabric is prepared, the fabric is washed in deionized water, impurity particles on the surface are removed, graphene powder with a single-layer or few-layer structure is further rubbed on the surface of the fabric for multiple times, certain pressure and temperature are applied in the process, and the conductive fabric is prepared. The preparation method comprises the following steps: preparing a graphene sheet layer under certain pressure, realizing good and uniform loading of the graphene sheet layer on the fiber surface, further removing the sheet layer with relatively small surface fastness in a high-pressure washing manner, drying, repeating the friction loading process under certain pressure, and finally realizing large-scale controllable preparation of the graphene modified conductive fabric. Due to a continuous conductive network and excellent conductivity, the conductive fabric can resist multiple times / various deformations, and is expected to be widely applied to the fields of electromagnetic shielding, electrochemical energy storage, static electricity resistance, wave absorption, electric heating and the like.

Description

Technical Field

[0001] The present invention belongs to the field of functional fabrics, and particularly relates to a graphene-based fabric with high conductivity, a preparation method thereof, and an application thereof. Background Art

[0002] In recent years, with the rapid development of wearable electronic devices, the demand for functional fabrics with good wearing properties and excellent conductivity has been increasing day by day. Due to its inherent high specific surface area, high conductivity, and excellent flexibility, graphene has attracted much attention since its discovery in 2004 and is expected to be applied in wearable electronic information, energy storage, energy conversion, etc. The fabric is generally obtained by specific weaving of polymer fibers. Since graphene itself lacks active groups on its surface, it is difficult to directly and uniformly load it on the surface of polymer fibers. Therefore, it is often necessary to modify the fabric or graphene to achieve the interaction between the two. In terms of fabric modification, the loading of graphene can be achieved by surface modification with polymer surfactants (J. Mater. Sci.-Mater. El., 2018, 29, 8010.), plasma treatment to increase the number of surface active groups (Synthetic Met., 2015, 202, 110.), and in-situ polymerization and loading of polydopamine (Mater. Chem. Phys., 2020, 241, 122371.). In terms of graphene modification, the interaction can be improved by reduction after loading graphene oxide (RSC Adv., 2014, 4, 23869.), chemical modification of graphene sheets with functional groups having active end groups (Adv. Mater. Interfaces, 2020, 7, 2000814.). However, the above methods have the following problems: (1) They all require surface modification and treatment of the fabric or graphene, which often leads to the loss of the functions of graphene and the fabric itself. For example, its conductivity and fabric strength often decrease; (2) In the actual production process, the modification and treatment are carried out in solution, and the processing flow is long, which often causes a large amount of unnecessary environmental pollution and energy waste.

[0003] Therefore, in order to overcome the problems of function loss and cumbersome process in the preparation of current conductive fabrics, it is urgent to develop a simpler and more effective processing method to achieve high conductivity and mechanical properties. Summary of the Invention

[0004] The purpose of the present invention is to provide a graphene-based fabric with high conductivity and a simple and easy-to-implement preparation method for the problems of cumbersome processing methods of current graphene-based conductive fabrics, poor conductivity and mechanical properties of functional fabrics, etc., so as to achieve the continuous and green preparation of high-conductivity functional fabrics.

[0005] To achieve the above object, according to the first aspect of the present invention, the following technical solutions are adopted by the present invention:

[0006] A highly conductive graphene-based fabric, characterized in that it has a structure in which graphene nanosheets wrap the fabric; wherein, the graphene is loaded by means of friction under pressure

[0007] Further, the fabric has a thickness of 0.5 to 5 mm, and the fabric structure is a woven fabric, a knitted fabric or a non-woven fabric.

[0008] Further, the fabric types include materials such as cotton fabric, polyester fabric, nylon fabric, polytetrafluoroethylene fabric, polyethylene fabric or polypropylene fabric.

[0009] To achieve the above object, according to the second aspect of the present invention, the following technical solutions are adopted by the present invention:

[0010] A method for preparing a highly conductive graphene-based fabric, characterized by comprising the following specific steps:

[0011] (1) Fabric surface cleaning: Soak the fabric material in deionized water and ethanol and ultrasonically clean it to remove surface impurities and grease, and then vacuum dry it for use in loading the conductive layer;

[0012] (2) Conductive layer loading: Using a grinding machine as the main loading tool, directly load the graphene powder on the fabric surface after multiple grindings under pressure conditions; enable the graphene sheets to fully contact and rub with the fabric surface to achieve in-situ loading on the surface;

[0013] (3) Fastness improvement: Wash the fabric surface with water flow to remove the graphene that is not fully loaded on the surface layer, improve the loading fastness of the conductive layer on the fabric surface, and further improve the stability of the conductive layer on the fabric surface. After drying, a graphene-modified conductive fabric is obtained;

[0014] (4) Repeated loading: Repeat the above steps (2) and (3) to further increase the loading amount of the conductive layer on the fabric surface and achieve the construction of the conductive fabric.

[0015] Further, the graphene is prepared by mechanical exfoliation method, electrochemical exfoliation method or chemical reduction of graphene oxide. The specific description is as follows: The graphene prepared by the mechanical exfoliation method is obtained after being treated by a grinding and dispersing machine; the graphene exfoliated by the electrochemical method is obtained by the three-electrode method; the graphene obtained by the chemical reduction method is obtained by reacting the graphene oxide prepared by the Hummers method in reducing agents such as hydroiodic acid, hydrazine hydrate, ascorbic acid, etc.

[0016] Further, the chassis of the grinding machine used is made of rubber material, the pressure range for grinding is 0.01 to 1 MPa, and the grinding time is 1 to 10 minutes.

[0017] Further, in the step (3), the flushing water pressure is 0.1 - 10 MPa, and the flushing time is 5 - 60 s.

[0018] Further, the number of repeated loads is 2 - 5 times

[0019] Further, in step (1), the fabric surface is ultrasonically treated for 10 min with a mixed solution of deionized water and ethanol with a volume ratio of 1:1 to remove particulate impurities and grease on the fabric surface. After washing with deionized water, it is dried in a vacuum oven at 40 °C for 6 h to obtain a fabric substrate with a clean surface.

[0020] The present invention loads graphene on the fabric surface by friction under a certain pressure. The method is simple and easy to implement, does not require surface modification of the fabric and graphene, and the prepared functional fabric has good electrical conductivity. Description of the Drawings

[0021] Figure 1 It is the SEM image of the surface of the graphene-modified fabric obtained in Example 4. Specific Embodiments:

[0022] The embodiments of the present invention are described below: These embodiments are implemented on the premise of the technical solution of the present invention, and detailed implementation methods and operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0023] Example 1

[0024] (1) Cleaning of the fabric surface: A 5×5 cm polypropylene non-woven fabric is placed in a mixed solution of deionized water and ethanol with a volume ratio of 1:1, ultrasonically washed for 10 min to remove particulate impurities and grease on the surface. Then, it is rinsed with ionized water and dried in a vacuum oven at 40 °C for 6 h to obtain a fabric substrate with a clean surface.

[0025] (2) Loading of the conductive layer: 1 g of graphene is evenly spread on the surface of the non-woven fabric. A grinding machine with a rubber chassis is selected as the loading tool. Under a pressure condition of 0.01 MPa, the graphene and the non-woven fabric are rubbed multiple times for 1 min using the grinding machine, so that the graphene sheets can be in full contact with the fabric surface and interact with each other to achieve in-situ loading on the surface.

[0026] (3) Improvement of fastness: First, the unloaded graphene on the fabric surface is removed by shaking. In order to further improve the adhesion of the graphene sheets on the fabric surface, the graphene-loaded fabric is flushed with a water stream at a pressure of 0.1 Mpa for 20 s to remove the graphene that is not fully loaded or has insufficient loading fastness on the surface layer, thereby improving the stability of the conductive layer on the fabric surface.

[0027] (4) Repeated loading: To obtain a highly conductive graphene-based conductive fabric, repeat the above steps (2) and (3) for the conductive fabric 2 times to increase the loading amount and fastness of graphene on the fabric surface, and finally achieve a conductive fabric with a conductivity of 20 Ω.

[0028] Example 2

[0029] (1) Fabric surface cleaning: Place a 5×5 cm knitted polyester fabric into a mixed solution of deionized water and ethanol with a volume ratio of 1:1, and wash it by ultrasonic for 10 min to remove the particulate impurities and grease on the surface. Then rinse it with ionized water and dry it in a vacuum oven at 40 °C for 6 h to obtain a fabric substrate with a clean surface.

[0030] (2) Conductive layer loading: Evenly disperse 1 g of graphene on the surface of the polyester fabric. Select a grinding machine with a rubber chassis as the loading tool. Under the condition of a pressure of 0.1 MPa, use the grinding machine to rub graphene and non-woven fabric multiple times for 2 min, so that the graphene sheets can be in full contact with the fabric surface and interact with each other to achieve in-situ loading on the surface.

[0031] (3) Fastness improvement: First, remove the unloaded graphene on the fabric surface by shaking. To further improve the adhesion of the graphene sheets on the fabric surface, rinse the graphene-loaded fabric with a water flow with a pressure of 0.5 Mpa for 5 s to remove the graphene that is not fully loaded or has insufficient loading fastness on the surface layer, thereby improving the stability of the conductive layer on the fabric surface.

[0032] (4) Repeated loading: To obtain a highly conductive graphene-based conductive fabric, repeat the above steps (2) and (3) for the conductive fabric 3 times to increase the loading amount and fastness of graphene on the fabric surface, and finally achieve a conductive fabric with a conductivity of 10 Ω.

[0033] Example 3

[0034] (1) Fabric surface cleaning: Place a 5×5 cm polytetrafluoroethylene fabric into a mixed solution of deionized water and ethanol with a volume ratio of 1:1, and wash it by ultrasonic for 10 min to remove the particulate impurities and grease on the surface. Then rinse it with ionized water and dry it in a vacuum oven at 40 °C for 6 h to obtain a fabric substrate with a clean surface.

[0035] (2) Conductive layer loading: Evenly disperse 1 g of graphene on the surface of the polytetrafluoroethylene fabric. Select a grinding machine with a rubber chassis as the loading tool. Under the condition of a pressure of 0.5 MPa, use the grinding machine to rub graphene and non-woven fabric multiple times for 5 min, so that the graphene sheets can be in full contact with the fabric surface and interact with each other to achieve in-situ loading on the surface.

[0036] (3) Fastness improvement: First, the unloaded graphene on the fabric surface is removed by shaking. To further enhance the adhesion of graphene sheets on the fabric surface, the graphene-loaded fabric is rinsed with a water stream at a pressure of 2 Mpa for 60 s to remove the graphene that is not fully loaded or has insufficient loading fastness on the surface layer, thereby improving the stability of the conductive layer on the fabric surface.

[0037] (4) Repeated loading: To obtain a highly conductive graphene-based conductive fabric, the above steps (2) and (3) are repeated 4 times for the conductive fabric to increase the loading amount and fastness of graphene on the fabric surface, and finally achieve a conductive fabric with a conductivity of 15 Ω.

[0038] Example 4

[0039] (1) Fabric surface cleaning: A 5×5 cm nylon fabric is placed in a mixed solution of deionized water and ethanol with a volume ratio of 1:1 and ultrasonically washed for 10 min to remove the particulate impurities and grease on the surface. Then, it is rinsed with ionized water and dried in a vacuum oven at 40 °C for 6 h to obtain a fabric substrate with a clean surface.

[0040] (2) Conductive layer loading: 1 g of graphene is evenly spread on the surface of the nylon fabric. A grinding machine with a rubber chassis is selected as the loading tool. Under a pressure of 1 MPa, the graphene and non-woven fabric are rubbed multiple times for 10 min using the grinding machine, enabling the graphene sheets to come into full contact with the fabric surface and interact with each other to achieve in-situ loading on the surface.

[0041] (3) Fastness improvement: First, the unloaded graphene on the fabric surface is removed by shaking. To further enhance the adhesion of graphene sheets on the fabric surface, the graphene-loaded fabric is rinsed with a water stream at a pressure of 10 Mpa for 40 s to remove the graphene that is not fully loaded or has insufficient loading fastness on the surface layer, thereby improving the stability of the conductive layer on the fabric surface. See Figure 1 .

[0042] (4) Repeated loading: To obtain a highly conductive graphene-based conductive fabric, the above steps (2) and (3) are repeated 5 times for the conductive fabric to increase the loading amount and fastness of graphene on the fabric surface, and finally achieve a conductive fabric with a conductivity of 7 Ω.

Claims

1. A graphene-based fabric with high electrical conductivity, characterized in that, It has a structure with graphene nanosheets wrapped on the surface of the fabric; among them, the graphene is loaded by the method of friction under pressing conditions.

2. The graphene-based fabric according to claim 1, wherein, The thickness of the fabric is 0.5 - 5 mm, and the fabric structure is woven fabric, knitted fabric or non-woven fabric.

3. The graphene-based fabric according to claim 1, wherein, The types of fabrics include cotton fabric, polyester fabric, nylon fabric, polytetrafluoroethylene fabric, polyethylene fabric or polypropylene fabric.

4. Preparation method of graphene-based fabric with high conductivity, characterized in that, It includes the following specific steps: (1) Cleaning the fabric surface: Soak the fabric material in deionized water and ethanol and ultrasonically clean it to remove surface impurities and grease, and use it for the loading of the conductive layer after vacuum drying. (2) Loading the conductive layer: Using a grinding machine as the main loading tool, load the graphene powder on the fabric surface after grinding under certain pressure conditions. (3) Improving the fastness: Wash the fabric surface with water flow to remove the graphene that is not fully loaded on the surface layer, improve the loading fastness of the conductive layer on the fabric surface, and obtain the graphene-modified conductive fabric after drying. (4) Repeated loading: Repeat steps (2) and (3) above to further increase the loading amount of the conductive layer on the fabric surface and realize the construction of the conductive fabric.

5. The preparation method of the graphene-based fabric according to claim 4, wherein, The graphene is prepared by mechanical exfoliation method, electrochemical exfoliation method or chemical reduction of graphene oxide.

6. The preparation method of the graphene-based fabric according to claim 4, characterized in that, The chassis of the grinding machine used is made of rubber material, the pressure range for grinding is 0.01 - 1 MPa, and the grinding time is 1 - 10 min.

7. The preparation method of the graphene-based fabric according to claim 4, wherein, In step (3), the flushing water pressure is 0.1 - 10 MPa, and the flushing time is 5 - 60 s.

8. The preparation method of the graphene-based fabric according to claim 4, characterized in that, The number of repeated loading times is 2 - 5 times.

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