Amphiphilic conductive carbon cloth and preparation method thereof

Abstract

The invention discloses amphiphilic conductive carbon cloth and a preparation method thereof, and belongs to the technical field of material preparation. The preparation method comprises the following steps: by taking an amphiphilic material (EAA) with strong adhesiveness as a modified material, firstly carrying out hydrophilic modification on the amphiphilic EAA, so as to improve the hydrophilicity of the amphiphilic EAA; the surface of the carbon cloth is sequentially coated with a bonding layer and an amphiphilic coating which are high in mass fraction through double-layer coating, the stability and hydrophilicity of the conductive carbon cloth are effectively improved on the premise that the conductivity of the carbon cloth is not affected, and the finally prepared conductive carbon cloth has the advantages of being high in conductivity, good in mechanical strength, hydrophilic and hydrophobic and the like. And the preparation method is simple, low in raw material price and mild in process condition, and can be widely applied to the fields of new energy, wires and cables, environmental protection, medicine, agriculture and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of material preparation, and particularly relates to an amphiphilic conductive carbon cloth and a preparation method thereof. Background Art

[0002] As an important conductive material, conductive carbon cloth has excellent electrical conductivity, good flexibility and stable chemical properties, so it has received extensive attention in various advanced applications such as energy storage devices, electronic devices, wires and cables, electro-chemical reactors and other fields. However, conductive carbon cloth still has some disadvantages in practical applications and needs to be solved by modification strategies. For example, the currently commonly used conductive carbon cloth has a smooth surface and strong hydrophobicity, which is not conducive to the deposition and growth of other hydrophilic materials when used as a substrate, and has poor stability in practical applications; the specific surface area and porosity of commercial conductive carbon cloth are relatively low, resulting in limited chemical activity and ion transport efficiency; in addition, although conductive carbon cloth has a certain flexibility, its mechanical strength and durability will gradually decline during long-term use, affecting the performance and life of the device.

[0003] To solve these problems, the current research hotspots mainly modify conductive carbon cloth through surface hydrophilization treatment, nanomaterial loading, composite material modification and structural design. However, due to the incompatibility between the modified material and conductive carbon cloth, there are often problems such as limited treatment effect, unstable hydrophilicity, and easy damage to the surface structure of the carbon cloth. In the traditional composite material modification method, fillers in the composite material such as nanoparticles or fibers are prone to aggregate in the matrix material, resulting in poor interfacial bonding of the conductive carbon cloth and local fluctuations in material properties. Moreover, in some applications, the bonding performance of the composite material is not good, resulting in low interfacial bonding force and serious peeling phenomenon. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an amphiphilic conductive carbon cloth and a preparation method thereof to solve the technical problem of poor surface hydrophilicity of conductive carbon cloth.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is: to provide a preparation method of an amphiphilic conductive carbon cloth, including the following steps:

[0006] S1. Immerse the carbon fiber felt in a glycerol solution for 10 - 30 min, then wash and dry it, and fix the treated carbon fiber felt on a substrate;

[0007] S2. Dissolve polyethylene acrylic acid (EAA) and an alkaline substance in an organic solvent at a mass ratio of 10 - 25:3 - 5, and react at 70 - 130 °C for 1 - 3 h to obtain sodium polyacrylate (EAANa);

[0008] Polyethylene acrylic acid is copolymerized from ethylene and acrylic acid monomers. Among them, the hydrophobic macromolecular chain polyethylene group plays functions such as enhancing material properties and regulating physical properties. The presence of carboxyl groups in acrylic acid monomers endows polyethylene acrylic acid with certain hydrophilicity. By alkalizing and modifying the amphiphilic substance EAA into EAANa, the hydrophilicity and stability of the conductive carbon cloth can be improved.

[0009] S3. Dissolve polyethylene acrylic acid and sodium polyacrylate in organic solvents respectively, react at 70 - 130 °C for 22 - 26 h to obtain casting solution A and casting solution B; then sequentially coat casting solution A and casting solution B on the surface of the carbon fiber felt after S1 treatment, and then place it in an organic solvent, soak at 5 - 30 °C for 22 - 26 h, remove the substrate to obtain amphiphilic conductive carbon cloth.

[0010] Based on the above technical solutions, the present invention can be further improved as follows:

[0011] Further, the mass fraction of the glycerol solution is 5 - 20%.

[0012] Further, the substrate is a glass plate.

[0013] Further, the alkaline substance is sodium hydroxide or potassium hydroxide.

[0014] Further, the organic solvent is N - N dimethylacetamide, N - N dimethylformamide or dimethylacetamide.

[0015] Further, in S2, the drying temperature is 80 - 105 °C and the drying time is 12 - 24 h.

[0016] Further, the mass fraction of casting solution A is 5 - 10%, and the mass fraction of casting solution B is 10 - 25%.

[0017] The present invention also discloses an amphiphilic conductive carbon cloth prepared by the above preparation method.

[0018] Based on the above technical solutions, the present invention can be further improved as follows:

[0019] Further, the structural layers of the amphiphilic conductive carbon cloth from bottom to top are successively: carbon fiber felt layer, polyethylene acrylic acid (EAA) layer, and sodium polyacrylate (EAANa) layer.

[0020] On the one hand, a small amount of EAA added in the traditional casting solution is intertwined with the molecular chains of EAANa in the coating layer, enhancing the adhesion stability of the coating layer; on the other hand, the high mass fraction of EAANa in the coating layer effectively solves the problems of less hydrophilic functional groups, dispersed molecular chains, insignificant improvement in hydrophilicity, and easy shedding of hydrophilic groups in the traditional casting solution.

[0021] Furthermore, the thickness of the amphiphilic conductive carbon cloth is 200 - 400 μm, the thickness of the carbon fiber felt layer is 80 - 300 μm, the thickness of the polyethylenemethacrylic acid layer is 10 - 50 μm, and the thickness of the polyethylenemethacrylic acid sodium layer is 50 - 150 μm.

[0022] The beneficial effects of the present invention are as follows:

[0023] 1. The present invention uses an amphiphilic material (EAA) with strong adhesiveness as a modification material. By first performing hydrophilic modification on the amphiphilic EAA to improve its hydrophilicity, and then through double-layer coating, a bonding layer with a higher mass fraction and an amphiphilic coating are sequentially coated on the surface of the carbon cloth, effectively improving the mechanical properties and hydrophilicity of the conductive carbon cloth without affecting its electrical conductivity.

[0024] 2. The process of the present invention is simple, the reaction conditions are mild, the raw materials are inexpensive and widely available, and the solid-liquid exchange reaction in the phase separation process greatly increases the specific surface area of the surface of the conductive carbon cloth, increasing the number of surface active sites and greatly enhancing the application prospects of the conductive carbon cloth in multiple fields such as energy storage, electrocatalysis, and environmental protection. Description of the Drawings

[0025] Figure 1 It is a comparative infrared spectrum diagram. Detailed Embodiments

[0026] The following describes the detailed embodiments of the present invention for the convenience of those skilled in the art to understand the present invention. For those not specified in the embodiments, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. For reagents or instruments not specified by the manufacturer, they are all conventional products that can be obtained through commercial purchase. However, it should be clear that the present invention is not limited to the scope of the detailed embodiments. For those ordinary skilled in the art, as long as various changes are within the spirit and scope of the present invention defined and determined by the appended claims, these changes are obvious, and all inventions and creations using the concept of the present invention are within the scope of protection.

[0027] Example 1

[0028] A preparation method of an amphiphilic conductive carbon cloth includes the following steps:

[0029] S1. Immerse a carbon fiber felt with a thickness of 80 μm in a 5 wt% glycerol solution for 30 min, then wash and dry it, and fix the treated carbon fiber felt on a glass plate.

[0030] S2. Dissolve 15 g of polyethylenemethacrylic acid (EAA) and 3 g of sodium hydroxide in 82 g of N-N dimethylacetamide, react at 70 °C for 3 h, then filter, wash the filtrate to neutral, and dry it at 80 °C for 24 h to obtain polyethylenemethacrylic acid sodium (EAANa).

[0031] S3. Dissolve 5 g of poly(ethyl acrylate) and 10 g of sodium poly(acrylate) in 100 g of N,N-dimethylacetamide respectively, and react at 70 °C for 24 h to obtain casting solution A and casting solution B; then coat casting solution A on the surface of the carbon fiber felt after S1 treatment with a thickness of 30 μm, then coat casting solution B on the surface of the poly(ethyl acrylate) layer with a thickness of 90 μm, then place it in N,N-dimethylacetamide and soak at 5 °C for 24 h, and finally wash and dry to obtain the amphiphilic conductive carbon cloth.

[0032] Example 2

[0033] A preparation method of an amphiphilic conductive carbon cloth, comprising the following steps:

[0034] S1. Immerse the carbon fiber felt with a thickness of 150 μm in an 8 wt% glycerol solution for 30 min, then wash and dry, and fix the treated carbon fiber felt on a glass plate;

[0035] S2. Dissolve 10 g of poly(ethyl acrylate) (EAA) and 5 g of sodium hydroxide in 85 g of N,N-dimethylacetamide, react at 70 °C for 1 h, then filter, wash the filtrate to neutral, and dry at 90 °C for 16 h to obtain sodium poly(acrylate) (EAANa);

[0036] S3. Dissolve 8 g of poly(ethyl acrylate) and 20 g of sodium poly(acrylate) in 100 g of N,N-dimethylacetamide respectively, and react at 70 °C for 24 h to obtain casting solution A and casting solution B; then coat casting solution A on the surface of the carbon fiber felt after S1 treatment with a thickness of 20 μm, then coat casting solution B on the surface of the poly(ethyl acrylate) layer with a thickness of 100 μm, then place it in N,N-dimethylacetamide and soak at 30 °C for 24 h, and finally wash and dry to obtain the amphiphilic conductive carbon cloth.

[0037] Example 3

[0038] A preparation method of an amphiphilic conductive carbon cloth, comprising the following steps:

[0039] S1. Immerse the carbon fiber felt with a thickness of 300 μm in a 15 wt% glycerol solution for 30 min, then wash and dry, and fix the treated carbon fiber felt on a glass plate;

[0040] S2. Dissolve 25 g of poly(ethyl acrylate) (EAA) and 3 g of potassium hydroxide in 72 g of N,N-dimethylacetamide, react at 70 °C for 2 h, then filter, wash the filtrate to neutral, and dry at 105 °C for 12 h to obtain sodium poly(acrylate) (EAANa);

[0041] S3. Dissolve 10 g of poly(ethylene acrylic acid) and 25 g of sodium poly(ethylene acrylate) in 100 g of N,N-dimethylacetamide respectively, and react at 70 °C for 24 h to obtain casting solution A and casting solution B; then coat casting solution A on the surface of the carbon fiber felt after S1 treatment with a thickness of 30 μm, then coat casting solution B on the surface of the poly(ethylene acrylic acid) layer with a thickness of 70 μm, then place it in N,N-dimethylacetamide, soak at 20 °C for 24 h, and finally wash and dry to obtain the amphiphilic conductive carbon cloth.

[0042] Example 4

[0043] A preparation method of an amphiphilic conductive carbon cloth, comprising the following steps:

[0044] S1. Immerse the carbon fiber felt with a thickness of 80 μm in a 15 wt% glycerol solution for 10 min, then wash and dry, and fix the treated carbon fiber felt on a glass plate;

[0045] S2. Dissolve 10 g of poly(ethylene acrylic acid) (EAA) and 5 g of potassium hydroxide in 85 g of N,N-dimethylformamide, react at 130 °C for 1 h, then filter, wash the filtrate to neutral, and dry at 80 °C for 12 h to obtain sodium poly(ethylene acrylate) (EAANa);

[0046] S3. Dissolve 10 g of poly(ethylene acrylic acid) and 15 g of sodium poly(ethylene acrylate) in 100 g of N,N-dimethylacetamide respectively, and react at 70 °C for 26 h to obtain casting solution A and casting solution B; then coat casting solution A on the surface of the carbon fiber felt after S1 treatment with a thickness of 10 μm, then coat casting solution B on the surface of the poly(ethylene acrylic acid) layer with a thickness of 150 μm, then place it in N,N-dimethylformamide, soak at 15 °C for 26 h, and finally wash and dry to obtain the amphiphilic conductive carbon cloth.

[0047] Example 5

[0048] A preparation method of an amphiphilic conductive carbon cloth, comprising the following steps:

[0049] S1. Immerse the carbon fiber felt with a thickness of 300 μm in a 20 wt% glycerol solution for 20 min, then wash and dry, and fix the treated carbon fiber felt on a glass plate;

[0050] S2. Dissolve 25 g of poly(ethylene acrylic acid) (EAA) and 4 g of sodium hydroxide in 71 g of N,N-dimethylformamide, react at 100 °C for 2 h, then filter, wash the filtrate to neutral, and dry at 105 °C for 24 h to obtain sodium poly(ethylene acrylate) (EAANa);

[0051] S3. Dissolve 5 g of poly(ethylene acrylic acid) and 25 g of sodium poly(ethylene acrylate) in 100 g of N,N-dimethylacetamide respectively, and react at 100 °C for 22 h to obtain casting solution A and casting solution B. Subsequently, coat casting solution A on the surface of the carbon fiber felt after S1 treatment with a thickness of 50 μm, then coat casting solution B on the surface of the poly(ethylene acrylic acid) layer with a thickness of 50 μm, then place it in N,N-dimethylformamide and soak at 25 °C for 22 h, and finally wash and dry to obtain the amphiphilic conductive carbon cloth.

[0052] Comparative example

[0053] The difference between this comparative example and Example 3 is that steps S2 and S3 are omitted to obtain the conductive carbon cloth after S1 treatment.

[0054] Take the conductive carbon cloths prepared in Examples 1 - 3 and the comparative example as samples, and conduct physical property tests on the carbon cloth samples. The data are shown in Table 1.

[0055] Table 1 Physical property data

[0056] Tensile strength (MPa) Conductivity (S / m) Water contact angle (°) <![CDATA[Specific surface area (m 2 / g)]]> Example 1 22.71 746.6 83.47 73.22 Example 2 25.93 727.1 76.57 83.21 Example 3 26.85 713.8 70.38 82.24 Comparative example 19.11 811.6 26.42 15.03

[0057] It can be seen from Table 1 that the tensile strength of the amphiphilic conductive carbon cloths prepared in Examples 1 - 3 is between 22.71 - 26.85 MPa, all higher than 19.11 MPa of the comparative example, indicating that the conductive carbon cloth prepared by the method of the present invention has excellent mechanical properties, can expand the application range, and extend the service life of the carbon cloth. At the same time, compared with the comparative example, the conductivity of Examples 1 - 3 decreases slightly, but still remains at a relatively high level above 700 S / m, while the water contact angle increases significantly, indicating that the method of the present invention effectively improves the mechanical stability and hydrophilicity of the conductive carbon cloth without affecting its conductivity. In addition, the specific surface area of Examples 1 - 3 shows an increasing trend of more than 4 times, indicating that the surface of the prepared amphiphilic conductive carbon cloth has abundant active sites, which can be used for further functional modification and expand the application fields.

[0058] Figure 1 It is the infrared spectrogram of the carbon cloths prepared in the comparative example and Examples 1 - 3. It can be seen from the figure that there are many new absorption peaks on the surface of the amphiphilic conductive carbon cloth membranes prepared in Examples 1 - 3, while there is no such situation for the conductive carbon cloth prepared in the comparative example. Among the newly added absorption peaks of the amphiphilic conductive carbon cloth, there are 2 characteristic peaks between 1404 cm -1 -1500 cm -1 for the bending vibration peaks of -CH2-, and 2 newly emerged characteristic peaks between 2851 cm -1 -2919 cm -1 for the asymmetric and symmetric stretching vibration peaks of -CH2- respectively; at 1264.59 cm-1 A new peak appears at -1 , caused by the bending vibration of C-O; at 1550.49 cm -1 There is one characteristic peak at -1 , which is the characteristic peak of the carboxylate group (COO-); in addition, at 1705.73 cm -1 There is also a peak at -1 , which is also caused by the C-O stretching vibration in the carboxylate group (COO-), indicating that EAA and EAANa have changed the surface of the conductive carbon cloth, endowing the carbon cloth surface with a large number of hydrophilic carboxyl groups and hydrophobic C-H molecular chains, making the carbon cloth have both hydrophilic and hydrophobic characteristics.

Claims

1. A preparation method of an amphiphilic conductive carbon cloth, characterized in that, It includes the following steps: S1. Immerse the carbon fiber felt in a glycerol solution for 10 - 30 min, then wash, dry, and fix the treated carbon fiber felt on a substrate; S2. Dissolve poly(acrylic acid) and an alkaline substance in an organic solvent at a mass ratio of 10 - 25:3 - 5, react at 70 - 130 °C for 1 - 3 h, then filter, wash, and dry the filtrate to obtain sodium polyacrylate; S3. Dissolve poly(acrylic acid) and sodium polyacrylate in an organic solvent respectively, react at 70 - 130 °C for 22 - 26 h to obtain casting solution A and casting solution B; then sequentially coat casting solution A and casting solution B on the surface of the carbon fiber felt treated in S1, then place it in an organic solvent, soak at 5 - 30 °C for 22 - 26 h, remove the substrate to obtain the amphiphilic conductive carbon cloth.

2. The preparation method of the amphiphilic conductive carbon cloth according to claim 1, wherein, The mass fraction of the glycerol solution is 5 - 20%.

3. The preparation method of the amphiphilic conductive carbon cloth according to claim 1, characterized in that, The substrate is a glass plate.

4. The preparation method of the amphiphilic conductive carbon cloth according to claim 1, characterized in that, The alkaline substance is sodium hydroxide or potassium hydroxide.

5. The preparation method of the amphiphilic conductive carbon cloth according to claim 1, characterized in that, The organic solvent is N,N - dimethylacetamide, N,N - dimethylformamide, or dimethylacetamide.

6. The preparation method of the amphiphilic conductive carbon cloth according to claim 1, wherein, In S2, the drying temperature is 80 - 105 °C and the drying time is 12 - 24 h.

7. The preparation method of the amphiphilic conductive carbon cloth according to claim 1, characterized in that, The mass fraction of casting solution A is 5 - 10%, and the mass fraction of casting solution B is 10 - 25%.

8. An amphiphilic conductive carbon cloth, characterized in that, It is prepared by the preparation method according to any one of claims 1 - 7.

9. The amphiphilic conductive carbon cloth according to claim 8, wherein The structural layers of the amphiphilic conductive carbon cloth from bottom to top are: carbon fiber felt layer, poly(acrylic acid) layer, and sodium polyacrylate layer.

10. The amphiphilic conductive carbon cloth according to claim 9, wherein, The thickness of the amphiphilic conductive carbon cloth is 200 - 400 μm, the thickness of the carbon fiber felt layer is 80 - 300 μm, the thickness of the poly(acrylic acid) layer is 10 - 50 μm, and the thickness of the sodium polyacrylate layer is 50 - 150 μm.

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