High-dispersity carbon nanotube slurry and preparation method thereof

Abstract

The invention relates to the technical field of carbon nanotube materials, in particular to high-dispersity carbon nanotube slurry and a preparation method thereof. Ammonium chloride, sodium azide, novolac epoxy resin and carbon nanotubes are added for modification treatment, and the modified carbon nanotubes are obtained. Then, a silane coupling agent KH550, an MXene material, a palmitic acid solution, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide are added and mixed, and the modified MXene material is obtained. And performing ultrasonic dispersion on polyvinylpyrrolidone, N-methyl pyrrolidone, the modified carbon nanotubes and the modified MXene material to obtain the composite conductive filler. The finished product is obtained by adding the surfactant, the deionized water and the composite conductive filler. The finished product prepared by the method has good conductivity and dispersity, so that the finished product has a wide application prospect in the technical field of carbon nanotube materials.

Description

Technical Field

[0001] The invention relates to the technical field of carbon nanotube materials, in particular to a highly dispersed carbon nanotube slurry and a preparation method thereof. Background Art

[0002] Carbon nanotube (CNTs) slurry has important value in modern science and technology and industry, which is mainly reflected in the following aspects: First, in the field of electronics and electrical, carbon nanotube slurry shows significant advantages in the field of electronics and electrical due to its excellent conductivity and good mechanical strength. CNTs slurry can be used to make conductive films, transparent conductive electrodes and high-performance cables. Its high conductivity makes CNTs widely used in thin film resistors, sensors and ultra-thin conductive layers. Second, in the field of energy storage, carbon nanotube slurry is widely used in the manufacture of supercapacitors and lithium-ion batteries. The high specific surface area and good conductivity of CNTs make it exhibit superior conductivity and high energy density in battery electrode materials. The use of CNTs slurry can significantly improve the charge and discharge rate, cycle life and overall energy density of the battery. In addition, CNTs slurry is also used in fuel cells to improve the efficiency and stability of electrocatalytic reactions. Third, in the field of environmental governance, carbon nanotube slurry shows good application prospects in environmental governance. CNTs have a high surface area and adsorption capacity and can be used as an adsorbent in water treatment and air purification. CNTs slurry can effectively remove harmful substances in water, such as heavy metal ions and organic pollutants, as well as harmful gases in the air, thereby achieving environmental pollution mitigation and control.

[0003] However, in practical applications, CNTs tend to form agglomerates, resulting in uneven dispersion, which affects the mechanical strength, conductivity and durability of the material. Therefore, it is crucial to improve the dispersion performance of carbon nanotube slurry. In addition, in order to give full play to the conductive advantages of CNTs, it is necessary to ensure that its conductive properties in the slurry are not affected. By improving the conductive properties of CNTs, the response speed of the device and the efficiency of electrical signal transmission can be increased, thereby improving the overall performance of the device.

[0004] In order to overcome the defects of the prior art, the present invention provides a highly dispersed carbon nanotube slurry and a preparation method thereof. Summary of the invention

[0005] The purpose of the present invention is to provide a highly dispersed carbon nanotube slurry and a preparation method thereof to solve the problems in the prior art.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] A method for preparing a highly dispersible carbon nanotube slurry comprises the following steps:

[0008] Step 1: adding ammonium chloride, sodium azide and phenolic epoxy resin to a solvent, stirring and reacting at 70-80°C for 8-9h, cooling, filtering, concentrating, extracting and drying after the reaction to obtain a modified epoxy resin; adding the modified epoxy resin and carbon nanotubes to N-methylpyrrolidone, reacting in an oil bath at 120-140°C under a nitrogen environment for 95-100h, cooling to 25-30°C after the reaction, filtering and vacuum drying to obtain modified carbon nanotubes;

[0009] Step 2: Disperse the MXene material in anhydrous ethanol, add the silane coupling agent KH550, and continue stirring to react for 20-25 hours. After the reaction is completed, centrifuge, wash, and dry to obtain an amino MXene material; dissolve the amino MXene material in HAc-NaAc buffer, add palmitic acid solution, cool in an ice bath, continue to add 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide, react in an ice water bath at 0-4°C for 1-2 hours, and then react at 25-30°C for 20-25 hours. After the reaction is completed, precipitate, filter, wash, and vacuum dry to obtain a modified MXene material;

[0010] Step 3: Add polyvinyl pyrrolidone and N-methyl pyrrolidone to deionized water, stir until dissolved, then add modified carbon nanotubes, ultrasonically disperse for 2-3 hours, shear for 5-7 hours, then add modified MXene material, ultrasonically disperse for 1-2 hours, and dry after dispersion to obtain a composite conductive filler;

[0011] Step 4: Add the surfactant to deionized water, stir thoroughly for 30-40 minutes, then add the composite conductive filler, grind to an average particle size of 7-8 μm, and obtain the finished product.

[0012] More optimally, in step one, the reaction mass ratio of ammonium chloride, sodium azide and phenolic epoxy resin is 0.3:2:(3-4); the solvent is composed of acetonitrile and deionized water in a volume ratio of (9-10):1.

[0013] More optimally, in step 1, the reaction mass ratio of the modified epoxy resin and the carbon nanotubes is (0.8-1.0):100.

[0014] More optimally, in step 2, the reaction mass ratio of MXene material and silane coupling agent KH550 is (8-10):35; palmitic acid is dissolved in dimethyl sulfoxide to obtain a palmitic acid solution; the pH of the HAc-NaAc buffer is 4.5-5.0.

[0015] More optimally, the preparation process of MXene material is as follows: add Ti3AlC2 powder to a mixture of lithium fluoride and hydrochloric acid, stir and react at 35-40°C for 30-35h, and after the reaction, wash the product to a pH of 6.0-6.5 to obtain MXene material; wherein the reaction mass ratio of Ti3AlC2 powder, lithium fluoride and hydrochloric acid is 1:1:(4.3-4.5).

[0016] More optimally, in step 2, the reaction mass ratio of the amino MXene material, palmitic acid, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide is (0.8-1.0): 5:2.5:0.5.

[0017] More optimally, in step three, the reaction mass ratio of polyvinyl pyrrolidone, N-methyl pyrrolidone, deionized water, modified carbon nanotubes and modified MXene materials is 10:10:200:1:(0.5-0.8).

[0018] More optimally, in step 4, the contents of the components of the finished product are: by mass fraction, 8-12% composite conductive filler, 2-3% surfactant, and the remainder is deionized water; the surfactant is sodium dodecyl sulfate.

[0019] Beneficial effects of the present invention:

[0020] The present invention is characterized in that, in step 1, a modified epoxy resin is obtained by adding ammonium chloride, sodium azide and phenolic epoxy resin; and the modified epoxy resin is used to modify carbon nanotubes to obtain modified carbon nanotubes. In this step, the phenolic epoxy resin containing epoxy groups first undergoes a ring-opening reaction with sodium azide under the catalytic action of ammonium chloride to prepare a modified epoxy resin; and then the modified epoxy resin having an azide group and carbon nanotubes are mixed to undergo an addition reaction, thereby grafting the modified epoxy resin onto the surface of the carbon nanotubes to obtain modified carbon nanotubes. The modified carbon nanotube filler prepared in this step has good dispersibility and effectively improves the agglomeration phenomenon of the carbon nanotube filler itself.

[0021] The feature of the present invention is that in step 2, an amino MXene material is obtained by adding a silane coupling agent KH550 and a MXene material; the amino MXene material, a palmitic acid solution, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide are mixed to obtain a modified MXene material. In this step, the MXene material is first modified using a silane coupling agent KH550 containing a functional amino group to obtain an amino MXene material; then, under the action of a 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride crosslinker and an N-hydroxysuccinimide crosslinker, the amino MXene material and palmitic acid are mixed and reacted to obtain a modified MXene material. This step modifies the MXene material using long-chain palmitic acid to obtain a modified MXene material with good dispersibility.

[0022] The feature of the present invention is that in step three and step four, the modified carbon nanotubes with good dispersibility and the modified MXene material are mixed in a mass ratio of 1: (0.5-0.8) to prepare a composite conductive filler; then the surfactant, deionized water and the composite conductive filler are mixed to obtain a finished slurry. In this step, the carbon nanotubes modified with tubular conductive materials and the MXene materials modified with layered conductive materials are compounded to form a network conductive structure to constitute an effective conductive path, thereby significantly improving the conductivity of the slurry. In summary, the finished slurry prepared by the present invention has good conductivity and dispersibility, and has broad application prospects in the field of carbon nanotube material technology. DETAILED DESCRIPTION

[0023] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Source of raw materials:

[0025] Carbon nanotubes, provided by Guangzhou Hongwu Materials Technology Co., Ltd., have a diameter of 2 nm; polyvinyl pyrrolidone, provided by Hubei Xinghengye Technology Co., Ltd., is industrial grade and has a molecular weight of 111; phenolic epoxy resin, provided by Nanya Electronic Materials, is NPPN-631; one portion is 1 g by mass.

[0026] Example 1: Step 1: Add ammonium chloride, sodium azide and phenolic epoxy resin to a solvent, stir and react at 80°C for 9 hours, and after the reaction is completed, cool, filter, concentrate, extract and dry to obtain a modified epoxy resin; add the modified epoxy resin and carbon nanotubes to N-methylpyrrolidone, react in a 140°C oil bath under a nitrogen environment for 100 hours, cool to 30°C after the reaction is completed, and then filter and vacuum dry to obtain modified carbon nanotubes; wherein the reaction mass ratio of ammonium chloride, sodium azide and phenolic epoxy resin is 0.3:2:3; the solvent is composed of acetonitrile and deionized water in a volume ratio of 10:1; the reaction mass ratio of modified epoxy resin and carbon nanotubes is 0.8:100;

[0027] Step 2: Add Ti3AlC2 powder to a mixture of lithium fluoride and hydrochloric acid, stir and react at 40°C for 35 hours, and wash the product to a pH of 6.5 after the reaction to obtain a MXene material; wherein the reaction mass ratio of Ti3AlC2 powder, lithium fluoride and hydrochloric acid is 1:1:4.5;

[0028] The MXene material was dispersed in anhydrous ethanol, and then the silane coupling agent KH550 was added and stirred for 25 hours. After the reaction, the material was centrifuged, washed and dried to obtain the amino MXene material. Palmitic acid was dissolved in dimethyl sulfoxide to obtain a palmitic acid solution. The amino MXene material was dissolved in HAc-NaAc buffer, and the palmitic acid solution was added. After cooling in an ice bath, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide were added. ℃ ice water bath for 2h, then at 30℃ for 25h, after the reaction, the modified MXene material was obtained by precipitation, filtration, washing and vacuum drying; wherein the reaction mass ratio of MXene material and silane coupling agent KH550 was 10:35; the pH of HAc-NaAc buffer was 5.0; the reaction mass ratio of amino MXene material, palmitic acid, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide was 1:5:2.5:0.5;

[0029] Step 3: Add polyvinyl pyrrolidone and N-methyl pyrrolidone to deionized water, stir until dissolved, then add modified carbon nanotubes, ultrasonically disperse for 3 hours, shear for 7 hours, then add modified MXene material, ultrasonically disperse for 2 hours, and dry after dispersion to obtain a composite conductive filler; the reaction mass ratio of polyvinyl pyrrolidone, N-methyl pyrrolidone, deionized water, modified carbon nanotubes and modified MXene material is 10:10:200:1:0.8;

[0030] Step 4: Add 3% sodium dodecyl sulfate to 87% deionized water by mass fraction, stir thoroughly for 40 minutes, add 10% composite conductive filler, grind to an average particle size of 7 μm, and obtain a finished product.

[0031] Example 2: Add ammonium chloride, sodium azide and phenolic epoxy resin to a solvent, stir and react at 75°C for 8.5 hours, and after the reaction is completed, cool, filter, concentrate, extract and dry to obtain a modified epoxy resin; add the modified epoxy resin and carbon nanotubes to N-methylpyrrolidone, react in a 130°C oil bath under a nitrogen environment for 97 hours, cool to 27°C after the reaction is completed, and then filter and vacuum dry to obtain modified carbon nanotubes; wherein the reaction mass ratio of ammonium chloride, sodium azide and phenolic epoxy resin is 0.3:2:3; the solvent is composed of acetonitrile and deionized water in a volume ratio of 10:1; the reaction mass ratio of modified epoxy resin and carbon nanotubes is 0.8:100;

[0032] Step 2: Add Ti3AlC2 powder to a mixture of lithium fluoride and hydrochloric acid, stir and react at 37°C for 33 hours, and wash the product to a pH of 6.3 after the reaction to obtain a MXene material; wherein the reaction mass ratio of Ti3AlC2 powder, lithium fluoride and hydrochloric acid is 1:1:4.5;

[0033] The MXene material was dispersed in anhydrous ethanol, and then the silane coupling agent KH550 was added and stirred for 23 hours. After the reaction, the material was centrifuged, washed and dried to obtain the amino MXene material. Palmitic acid was dissolved in dimethyl sulfoxide to obtain a palmitic acid solution. The amino MXene material was dissolved in HAc-NaAc buffer, and the palmitic acid solution was added. After cooling in an ice bath, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide were added. The mixture was incubated at 2°C. The reaction was carried out in an ice-water bath for 1.5 hours, and then at 28°C for 23 hours. After the reaction was completed, the modified MXene material was obtained by precipitation, filtration, washing, and vacuum drying. The reaction mass ratio of the MXene material and the silane coupling agent KH550 was 10:35. The pH of the HAc-NaAc buffer was 4.7. The reaction mass ratio of the amino MXene material, palmitic acid, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride, and N-hydroxysuccinimide was 1:5:2.5:0.5.

[0034] Step 3: Add polyvinyl pyrrolidone and N-methyl pyrrolidone to deionized water, stir until dissolved, then add modified carbon nanotubes, ultrasonically disperse for 2.5 hours, shear for 6 hours, then add modified MXene material, ultrasonically disperse for 1.5 hours, and dry after dispersion to obtain a composite conductive filler; the reaction mass ratio of polyvinyl pyrrolidone, N-methyl pyrrolidone, deionized water, modified carbon nanotubes and modified MXene material is 10:10:200:1:0.8;

[0035] Step 4: By mass fraction, add 3% sodium dodecyl sulfate to 87% deionized water, stir thoroughly for 35 minutes, then add 10% composite conductive filler, grind to an average particle size of 7 μm, and obtain a finished product.

[0036] Example 3: Step 1: Add ammonium chloride, sodium azide and phenolic epoxy resin to a solvent, stir and react at 70°C for 8 hours, and after the reaction is completed, cool, filter, concentrate, extract and dry to obtain a modified epoxy resin; add the modified epoxy resin and carbon nanotubes to N-methylpyrrolidone, react in a 120°C oil bath under a nitrogen environment for 95 hours, cool to 25°C after the reaction is completed, and then filter and vacuum dry to obtain modified carbon nanotubes; wherein the reaction mass ratio of ammonium chloride, sodium azide and phenolic epoxy resin is 0.3:2:3; the solvent is composed of acetonitrile and deionized water in a volume ratio of 10:1; the reaction mass ratio of modified epoxy resin and carbon nanotubes is 0.8:100;

[0037] Step 2: Add Ti3AlC2 powder to a mixture of lithium fluoride and hydrochloric acid, stir and react at 35°C for 30 hours, and wash the product to a pH of 6.0 after the reaction to obtain a MXene material; wherein the reaction mass ratio of Ti3AlC2 powder, lithium fluoride and hydrochloric acid is 1:1:4.5;

[0038] The MXene material was dispersed in anhydrous ethanol, and then the silane coupling agent KH550 was added and stirred for 20 hours. After the reaction, the material was centrifuged, washed and dried to obtain the amino MXene material. Palmitic acid was dissolved in dimethyl sulfoxide to obtain a palmitic acid solution. The amino MXene material was dissolved in HAc-NaAc buffer, and the palmitic acid solution was added. After cooling in an ice bath, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide were added. ℃ ice water bath for 1h, and then at 25℃ for 20h. After the reaction, the modified MXene material was obtained by precipitation, filtration, washing and vacuum drying. The reaction mass ratio of MXene material and silane coupling agent KH550 was 10:35. The pH of HAc-NaAc buffer was 4.5. The reaction mass ratio of amino MXene material, palmitic acid, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide was 1:5:2.5:0.5.

[0039] Step 3: Add polyvinyl pyrrolidone and N-methyl pyrrolidone to deionized water, stir until dissolved, then add modified carbon nanotubes, ultrasonically disperse for 2 hours, shear for 5 hours, then add modified MXene material, ultrasonically disperse for 1 hour, and dry after dispersion to obtain a composite conductive filler; the reaction mass ratio of polyvinyl pyrrolidone, N-methyl pyrrolidone, deionized water, modified carbon nanotubes and modified MXene material is 10:10:200:1:0.8;

[0040] Step 4: Add 3% sodium dodecyl sulfate to 87% deionized water by mass fraction, stir thoroughly for 30 minutes, add 10% composite conductive filler, grind to an average particle size of 7 μm, and obtain a finished product.

[0041] Comparative Example 1: The modified carbon nanotubes were replaced with carbon nanotubes provided by Guangzhou Hongwu Materials Technology Co., Ltd., and the rest was the same as Example 1, and the specific steps were as follows: Step 1: Ti3AlC2 powder was added to a mixture of lithium fluoride and hydrochloric acid, and the mixture was stirred at 40°C for 35 hours. After the reaction, the product was washed to a pH of 6.5 to obtain a MXene material; wherein the reaction mass ratio of Ti3AlC2 powder, lithium fluoride and hydrochloric acid was 1:1:4.5;

[0042] The MXene material was dispersed in anhydrous ethanol, and then the silane coupling agent KH550 was added and stirred for 25 hours. After the reaction, the material was centrifuged, washed and dried to obtain the amino MXene material. Palmitic acid was dissolved in dimethyl sulfoxide to obtain a palmitic acid solution. The amino MXene material was dissolved in HAc-NaAc buffer, and the palmitic acid solution was added. After cooling in an ice bath, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide were added. ℃ ice water bath for 2h, then at 30℃ for 25h, after the reaction, the modified MXene material was obtained by precipitation, filtration, washing and vacuum drying; wherein the reaction mass ratio of MXene material and silane coupling agent KH550 was 10:35; the pH of HAc-NaAc buffer was 5.0; the reaction mass ratio of amino MXene material, palmitic acid, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide was 1:5:2.5:0.5;

[0043] Step 2: Add polyvinyl pyrrolidone and N-methyl pyrrolidone to deionized water, stir until dissolved, then add carbon nanotubes, ultrasonically disperse for 3 hours, shear for 7 hours, then add modified MXene material, ultrasonically disperse for 2 hours, and dry after dispersion to obtain a composite conductive filler; the reaction mass ratio of polyvinyl pyrrolidone, N-methyl pyrrolidone, deionized water, carbon nanotubes and modified MXene material is 10:10:200:1:0.8;

[0044] Step 3: By mass fraction, add 3% sodium dodecyl sulfate to 87% deionized water, stir thoroughly for 40 minutes, then add 10% composite conductive filler, grind to an average particle size of 7 μm, and obtain a finished product.

[0045] Comparative Example 2: The modified MXene material is replaced with the MXene material prepared by the present invention, and the rest is the same as Example 1, and the specific steps are as follows: Step 1: Add ammonium chloride, sodium azide and phenolic epoxy resin to the solvent, stir and react at 80°C for 9 hours, and after the reaction is completed, cool, filter, concentrate, extract and dry to obtain a modified epoxy resin; add the modified epoxy resin and carbon nanotubes to N-methylpyrrolidone, react in a 140°C oil bath under a nitrogen environment for 100 hours, cool to 30°C after the reaction is completed, and then filter and vacuum dry to obtain modified carbon nanotubes; wherein the reaction mass ratio of ammonium chloride, sodium azide and phenolic epoxy resin is 0.3:2:3; the solvent is composed of acetonitrile and deionized water in a volume ratio of 10:1; the reaction mass ratio of the modified epoxy resin and the carbon nanotubes is 0.8:100;

[0046] Step 2: Add polyvinyl pyrrolidone and N-methyl pyrrolidone to deionized water, stir until dissolved, then add modified carbon nanotubes, ultrasonically disperse for 3 hours, shear for 7 hours, then add MXene material, ultrasonically disperse for 2 hours, and dry after dispersion to obtain a composite conductive filler; the reaction mass ratio of polyvinyl pyrrolidone, N-methyl pyrrolidone, deionized water, modified carbon nanotubes and MXene material is 10:10:200:1:0.8;

[0047] Step 3: By mass fraction, add 3% sodium dodecyl sulfate to 87% deionized water, stir thoroughly for 40 minutes, then add 10% composite conductive filler, grind to an average particle size of 7 μm, and obtain a finished product.

[0048] Comparative Example 3: The mass ratio of modified carbon nanotubes and modified MXene materials was changed from 1: (0.5-0.8) to 1: 0.3, and the rest was the same as Example 1, and the specific steps were as follows: Step 1: Add ammonium chloride, sodium azide and phenolic epoxy resin to the solvent, stir and react at 80°C for 9 hours, and after the reaction, cool, filter, concentrate, extract and dry to obtain a modified epoxy resin; add the modified epoxy resin and carbon nanotubes to N-methylpyrrolidone, react in a 140°C oil bath under a nitrogen environment for 100 hours, cool to 30°C after the reaction, and then filter and vacuum dry to obtain modified carbon nanotubes; wherein the reaction mass ratio of ammonium chloride, sodium azide and phenolic epoxy resin is 0.3:2:3; the solvent is composed of acetonitrile and deionized water in a volume ratio of 10:1; the reaction mass ratio of modified epoxy resin and carbon nanotubes is 0.8:100;

[0049] Step 2: Add Ti3AlC2 powder to a mixture of lithium fluoride and hydrochloric acid, stir and react at 40°C for 35 hours, and wash the product to a pH of 6.5 after the reaction to obtain a MXene material; wherein the reaction mass ratio of Ti3AlC2 powder, lithium fluoride and hydrochloric acid is 1:1:4.5;

[0050] The MXene material was dispersed in anhydrous ethanol, and then the silane coupling agent KH550 was added and stirred for 25 hours. After the reaction, the material was centrifuged, washed and dried to obtain the amino MXene material. Palmitic acid was dissolved in dimethyl sulfoxide to obtain a palmitic acid solution. The amino MXene material was dissolved in HAc-NaAc buffer, and the palmitic acid solution was added. After cooling in an ice bath, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide were added. ℃ ice water bath for 2h, then at 30℃ for 25h, after the reaction, the modified MXene material was obtained by precipitation, filtration, washing and vacuum drying; wherein the reaction mass ratio of MXene material and silane coupling agent KH550 was 10:35; the pH of HAc-NaAc buffer was 5.0; the reaction mass ratio of amino MXene material, palmitic acid, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide was 1:5:2.5:0.5;

[0051] Step 3: Add polyvinyl pyrrolidone and N-methyl pyrrolidone to deionized water, stir until dissolved, then add modified carbon nanotubes, ultrasonically disperse for 3 hours, shear for 7 hours, then add modified MXene material, ultrasonically disperse for 2 hours, and dry after dispersion to obtain a composite conductive filler; the reaction mass ratio of polyvinyl pyrrolidone, N-methyl pyrrolidone, deionized water, modified carbon nanotubes and modified MXene material is 10:10:200:1:0.3;

[0052] Step 4: Add 3% sodium dodecyl sulfate to 87% deionized water by mass fraction, stir thoroughly for 40 minutes, add 10% composite conductive filler, grind to an average particle size of 7 μm, and obtain a finished product.

[0053] Detection test:

[0054] Conductivity test: The finished slurry prepared by the present invention is coated on a polyimide insulating substrate with a 300 μm scraper and dried at 100° C. for 60 min. The obtained carbon film is subjected to roller pressing and used as a sample. The conductivity of the film is tested by using a four-probe method.

[0055] Slurry stability test: The finished slurry prepared by the present invention was placed in a room temperature environment for 3 months, and the conductivity of the carbon film after coating was tested. The conductivity of the carbon film coated with the finished slurry after 3 months was obtained, and the stability of the slurry was evaluated by calculating the percentage of the change in the initial conductivity relative to the initial conductivity. The results are shown in the following table:

[0056] Conductivity / (S / cm) Conductivity change rate / (%) Example 1 370 2.3 Example 2 367 2.4 Example 3 365 2.6 Comparative Example 1 344 3.8 Comparative Example 2 353 2.9 Comparative Example 3 310 2.4

[0057] Conclusion: The dosage of Examples 1 to 3 remains unchanged, and only some reaction parameters are modified. From the experimental data, it can be seen that there is no obvious fluctuation in the performance of the samples.

[0058] Comparative Example 1: The modified carbon nanotubes are replaced with carbon nanotubes provided by Guangzhou Hongwu Material Technology Co., Ltd., and the rest are the same as Example 1. It can be seen from the experimental data that compared with Example 1, the conductivity is reduced to 344S / cm, and the conductivity change rate is increased by 3.8%. The reason is analyzed as follows: the modified carbon nanotubes prepared by the present invention have good dispersibility, can effectively improve the agglomeration phenomenon, enhance the stability of the slurry, and enhance the conductivity of the slurry. Therefore, after replacing the modified carbon nanotubes with the carbon nanotubes provided by Guangzhou Hongwu Material Technology Co., Ltd., the stability of the slurry is reduced, the conductivity is reduced, and the conductivity change rate is increased.

[0059] Comparative Example 2: The modified MXene material is replaced by the MXene material prepared by the present invention, and the rest is the same as Example 1. It can be seen from the experimental data that compared with Example 1, the conductivity is reduced to 353S / cm, and the conductivity change rate is increased by 2.9%. The reason is analyzed as follows: the modified MXene material prepared by the present invention has good dispersibility after palmitic acid modification, which can effectively improve the agglomeration phenomenon, improve the stability of the slurry, and improve the conductivity of the slurry. Therefore, after the modified MXene material is replaced by the MXene material prepared by the present invention, the stability of the slurry is reduced, the conductivity is reduced, and the conductivity change rate is increased.

[0060] Comparative Example 3: The mass ratio of modified carbon nanotubes and modified MXene materials was changed from 1: (0.5-0.8) to 1: 0.3, and the rest was the same as Example 1. It can be seen from the experimental data that compared with Example 1, the conductivity was reduced to 310S / cm. The reason was analyzed as follows: after the modified carbon nanotubes and modified MXene materials were effectively compounded according to 1: (0.5-0.8), a conductive network structure with an effective conductive path could be obtained, but when the ratio exceeded this range, the modified carbon nanotubes and modified MXene materials could not be effectively mixed and compounded to form a conductive network, so the conductive performance decreased and the conductivity decreased.

[0061] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process method article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process method article or device.

[0062] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a highly dispersed carbon nanotube slurry, characterized in that: The following steps are involved: Step 1: adding ammonium chloride, sodium azide and phenolic epoxy resin to a solvent, stirring and reacting at 70-80° C. for 8-9 hours, and cooling, filtering, concentrating, extracting and drying after the reaction to obtain a modified epoxy resin; Adding the modified epoxy resin and carbon nanotubes to N-methylpyrrolidone, reacting in an oil bath at 120-140° C. for 95-100 hours under a nitrogen environment, cooling to 25-30° C. after the reaction, filtering and vacuum drying to obtain modified carbon nanotubes; Step 2: Disperse the MXene material in anhydrous ethanol, add the silane coupling agent KH550, and continue stirring to react for 20-25 hours. After the reaction is completed, centrifuge, wash, and dry to obtain an amino MXene material; dissolve the amino MXene material in HAc-NaAc buffer, add palmitic acid solution, cool in an ice bath, continue to add 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide, react in an ice water bath at 0-4°C for 1-2 hours, and then react at 25-30°C for 20-25 hours. After the reaction is completed, precipitate, filter, wash, and vacuum dry to obtain a modified MXene material; Step 3: Add polyvinyl pyrrolidone and N-methyl pyrrolidone to deionized water, stir until dissolved, then add modified carbon nanotubes, ultrasonically disperse for 2-3 hours, shear for 5-7 hours, then add modified MXene material, ultrasonically disperse for 1-2 hours, and dry after dispersion to obtain a composite conductive filler; Step 4: Add the surfactant to deionized water, stir thoroughly for 30-40 minutes, then add the composite conductive filler, grind to an average particle size of 7-8 μm, and obtain the finished product.

2. The method for preparing a highly dispersed carbon nanotube slurry according to claim 1, characterized in that: In step 1, the reaction mass ratio of ammonium chloride, sodium azide and phenolic epoxy resin is 0.3:2:(3-4); the solvent is composed of acetonitrile and deionized water in a volume ratio of (9-10):

1.

3. The method for preparing a highly dispersed carbon nanotube slurry according to claim 1, characterized in that: In step 1, the reaction mass ratio of the modified epoxy resin and the carbon nanotubes is (0.8-1.0):

100.

4. The method for preparing a highly dispersed carbon nanotube slurry according to claim 1, characterized in that: In step 2, the reaction mass ratio of MXene material and silane coupling agent KH550 is (8-10):35; palmitic acid is dissolved in dimethyl sulfoxide to obtain a palmitic acid solution; the pH of the HAc-NaAc buffer is 4.5-5.

0.

5. The method for preparing a highly dispersed carbon nanotube slurry according to claim 4, characterized in that: The preparation process of MXene material is as follows: add Ti3AlC2 powder to a mixture of lithium fluoride and hydrochloric acid, stir and react at 35-40°C for 30-35 hours, and after the reaction, wash the product to a pH of 6.0-6.5 to obtain MXene material; wherein the reaction mass ratio of Ti3AlC2 powder, lithium fluoride and hydrochloric acid is 1:1:(4.3-4.5).

6. The method for preparing a highly dispersed carbon nanotube slurry according to claim 1, characterized in that: In step 2, the reaction mass ratio of the amino MXene material, palmitic acid, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide is (0.8-1.0): 5: 2.5: 0.

5.

7. The method for preparing a highly dispersed carbon nanotube slurry according to claim 1, characterized in that: In step three, the reaction mass ratio of polyvinyl pyrrolidone, N-methyl pyrrolidone, deionized water, modified carbon nanotubes and modified MXene material is 10:10:200:1:(0.5-0.8).

8. The method for preparing a highly dispersed carbon nanotube slurry according to claim 1, characterized in that: In step 4, the contents of the components of the finished product are: by mass fraction, 8-12% of composite conductive filler, 2-3% of surfactant, and the remainder is deionized water; the surfactant is sodium dodecyl sulfate.