阅读说明：本技术 一种超导易分散石墨烯粉体的制备方法及其在导电塑料中的应用 (Preparation method of superconducting easily-dispersible graphene powder and application of superconducting easily-dispersible graphene powder in conductive plastics ) 是由 邢飞 吴田鸽 李宗文 韩雪 田敬坤 姬广民 于 2021-01-08 设计创作，主要内容包括：本发明公开了一种超导易分散石墨烯粉体的制备方法及其在导电塑料中的应用。在酸性环境下对石墨烯进行改性,减小石墨烯片层间的范德华力,与此同时,不会破坏石墨烯的本质。通过对石墨烯粉体进行改性技术,得到的石墨烯粉体分散性好,与其他材料具有良好的融合性,石墨烯的导电性亦明显得到改善。并且在普通塑料中加入改性石墨烯,二者可以很好的融合,得到一种导电性、导热性良好的导电塑料。(The invention discloses a preparation method of superconducting easily-dispersible graphene powder and application of the superconducting easily-dispersible graphene powder in conductive plastics. The graphene is modified in an acid environment, so that van der Waals force between graphene sheets is reduced, and meanwhile, the essence of the graphene is not damaged. The graphene powder obtained by the modification technology has good dispersibility, has good fusion with other materials, and the conductivity of the graphene is also obviously improved. And the modified graphene is added into the common plastic, and the modified graphene and the common plastic can be well fused to obtain the conductive plastic with good electrical conductivity and thermal conductivity.)

1. The preparation of the super-dispersible graphene powder aims to modify the graphene powder, and the super-dispersible graphene is well fused with plastic to obtain a soft plastic film with good electrical conductivity and thermal conductivity.

2. The preparation method of the ultra-easily dispersible graphene powder as claimed in claim 1, comprising the following steps:

1) washing graphene with water, and removing residues except the graphene until the washing liquid is colorless and transparent, and the pH value is 7;

2) carrying out micro-carbonization treatment on graphene, namely dehydrating the washed graphene obtained in the step 1), and drying the washed graphene at a low temperature in vacuum to slightly increase the content of disordered carbon on the surface of the obtained graphene;

3) infiltrating the graphene powder obtained in the step 2), and according to the following steps: silicone oil: the mass ratio of water is 1 (0.5-2) to 4-10, and the mixture is evenly mixed and soaked for 10-30 min;

4) preparing a graphene surface modifier according to the following steps of: ethyl orthosilicate: preparing a surface modifier by formaldehyde = (2-10): (1-5): (0.001-0.01), and performing ultrasonic treatment for 20min, wherein silicon generated after hydrolysis of tetraethoxysilane can be attached to the surface of a graphene film, and the formaldehyde is used as a graphene polymerization inhibitor and can reduce van der Waals force between graphene sheets;

5) uniformly mixing the infiltrated graphene obtained in the step 3) with a surface modifier, performing ultrasonic treatment for 16-36 h, wherein the mass ratio of the graphene to the surface modifier is 1 (50-200), washing with water until the pH value of the graphene aqueous solution is neutral after the ultrasonic treatment is finished, and performing ultrasonic treatment for 4-8h, and then performing dehydration filtration;

6) putting the graphene filter cake obtained in the step 5) into a phosphoric acid aqueous solution for ultrasonic dispersion, slowly dropping ammonium tungsten phosphate solution in the ultrasonic dispersion process, performing ultrasonic cleaning for 24h, dehydrating and cleaning until the pH value is neutral, dehydrating, and performing vacuum drying at low temperature to obtain the superconductive easily-dispersed graphene, wherein the mass of the graphene and the phosphoric acid solution is 1 (100) and the concentration of the phosphoric acid solution is 10-30%; the mass of the ammonium tungsten phosphate solution is 0.1-1 time of that of phosphoric acid, and the concentration is 5% -30%.

3. The method for preparing the ultra-dispersible graphene powder according to claim 2, wherein the low-temperature vacuum drying temperature of the ultra-dispersible graphene is 10-90 ℃, and the drying time is 6-36 h.

4. The method according to claim 2, wherein the silicone oil for impregnating the super-dispersible graphene powder comprises at least one of dimethyl silicone oil, ethyl silicone oil, phenyl silicone oil, methyl hydrogen silicone oil, methylphenyl silicone oil, methyl chlorophenyl silicone oil, methyl ethoxy silicone oil, methyl vinyl silicone oil, methyl hydroxy silicone oil, ethyl hydrogen silicone oil, hydroxy hydrogen silicone oil, and cyanogen-containing silicone oil.

5. The method according to claim 2, wherein the acidic environment of the super-dispersible graphene is at least one of hydrochloric acid, sulfuric acid, nitric acid, perchloric acid, hydroiodic acid, and hydrobromic acid with a concentration of 5% to 20%.

6. A preparation method of conductive plastic comprises the following steps:

heating and melting a plastic raw material, adding the superconductive dispersible graphene powder, uniformly stirring, and molding.

7. The preparation of the conductive plastic of claim 6, wherein the mass ratio of the addition amount of the graphene in the conductive plastic is 0.05-5%.

8. The method of producing an electrically conductive plastic as claimed in claim 6, wherein the plastic raw material comprises at least one of polyethylene, polypropylene, polyvinyl chloride, polystyrene, polymethacrylate, polybutylene terephthalate, and polycarbonate resin.

9. The preparation of an electrically conductive plastic as claimed in claim 6, characterized in that the heating temperature of the plastic raw material is 70 to 250 ℃.

Technical Field

The invention relates to the field of graphene preparation, in particular to a preparation method and application of graphene powder.

Background

Graphene is a novel nanomaterial, a two-dimensional atomic material with a hexagonal honeycomb crystal structure, and is formed by sp atoms of carbon²The hybrid material is a novel nano material which is the thinnest, the maximum strength and the strongest electric and heat conducting performance and is called as 'black gold' and 'king of new material' and has wide application prospect in the fields of physics, materials science and the like.

The graphene has a single-substance structure, a special curved surface structure, a large specific surface area and large van der Waals force between layers, so that the graphene is difficult to share with other materials. In simple liquid phase dispersion application, for example, graphene added in ink as an electric conductor can be uniformly dispersed in an ink solvent, but the graphene and the ink have no good fusion property at all, and only exist in suspension in the ink. As the ink dries and cures, the rigid and curved structure of the graphene can cause the graphene-containing coating to deform and peel off. Graphene has excellent conductivity, but is extremely easy to agglomerate and disperse due to van der waals force between the sheet layers, so that the conductivity of the graphene is general. In solid-solid dispersion application, the fusion of graphene and other materials is poorer, and the application prospect of graphene is severely limited.

Disclosure of Invention

Aiming at the problem of poor fusion of graphene and a solid material, the invention aims to modify graphene powder to obtain superconducting easily-dispersible graphene powder. The second purpose of the invention is to add the modified graphene powder into the conventional plastic, so that the superconducting easily-dispersed graphene and the plastic are well fused to obtain the flexible plastic film with good electrical and thermal conductivity.

The technical scheme adopted by the invention is as follows:

a preparation method of superconducting easily-dispersed graphene powder comprises the following steps:

1) and (3) washing the graphene with water, and removing residues except the graphene until the washing liquid is colorless and transparent, and the pH value is 7.

2) Carrying out micro-carbonization treatment on the graphene, dehydrating the washed graphene obtained in the step 1), and drying the washed graphene in vacuum at low temperature to slightly increase the content of disordered carbon on the surface of the obtained graphene.

3) Infiltrating the graphene powder obtained in the step 2), and according to the following steps: silicone oil: the mass ratio of water is 1 (0.5-2) to 4-10, and the mixture is evenly mixed and soaked for 10-30 min. Wherein the silicone oil comprises at least one of dimethyl silicone oil, ethyl silicone oil, phenyl silicone oil, methyl hydrogen-containing silicone oil, methyl phenyl silicone oil, methyl chlorphenyl silicone oil, methyl ethoxy silicone oil, methyl vinyl silicone oil, methyl hydroxyl silicone oil, ethyl hydrogen-containing silicone oil, hydroxyl hydrogen-containing silicone oil and cyanogen-containing silicone oil.

4) And preparing the graphene surface modifier. Under an acidic environment (at least one of hydrochloric acid, sulfuric acid, nitric acid, perchloric acid, hydroiodic acid and hydrobromic acid with the concentration of 5% -20%), according to the weight ratio of ethyl acetate: ethyl orthosilicate: formaldehyde = (2-10): (1-5): (0.001-0.01) and ultrasonic treatment is carried out for 20 min. The silicon generated after hydrolysis of the tetraethoxysilane can be attached to the surface of the graphene film, and the formaldehyde is used as a graphene polymerization inhibitor, so that the van der Waals force between graphene sheets can be reduced.

5) Uniformly mixing the infiltrated graphene obtained in the step 3) with a surface modifier, performing ultrasonic treatment for 16-36 h, wherein the mass ratio of the graphene to the surface modifier is 1 (50-200), washing with water until the pH value of the graphene aqueous solution is neutral after the ultrasonic treatment is finished, and performing ultrasonic treatment for 4-8h, and then performing dehydration filtration.

6) And (3) putting the graphene filter cake obtained in the step 5) into a phosphoric acid aqueous solution for ultrasonic dispersion, slowly dropping a tungsten ammonium phosphate solution in the ultrasonic dispersion process, performing ultrasonic treatment for 24 hours, dehydrating and cleaning until the pH value is neutral, dehydrating, and performing vacuum drying at a low temperature to obtain the superconductive easily-dispersed graphene. Wherein the mass of the graphene and the phosphoric acid solution is 1 (100-500), and the concentration of the phosphoric acid solution is 10-30%; the mass of the ammonium tungsten phosphate solution is 0.1-1 time of that of phosphoric acid, and the concentration is 5% -30%.

A preparation method of conductive plastic comprises the following steps:

heating and melting a plastic raw material, adding the superconductive dispersible graphene powder, uniformly stirring, and molding.

The preparation method of the superconducting easily-dispersible graphene, disclosed by the invention, has the advantages that the low-temperature vacuum drying temperature of the superconducting easily-dispersible graphene is 10-90 ℃, and the drying time is 6-36 h.

The preparation method of the superconducting easily-dispersible graphene comprises the step of soaking the graphene powder with silicone oil, wherein the silicone oil comprises at least one of dimethyl silicone oil, ethyl silicone oil, phenyl silicone oil, methyl hydrogen-containing silicone oil, methyl phenyl silicone oil, methyl chlorphenyl silicone oil, methyl ethoxy silicone oil, methyl vinyl silicone oil, methyl hydroxyl silicone oil, ethyl hydrogen-containing silicone oil, hydroxyl hydrogen-containing silicone oil and cyanogen-containing silicone oil.

The preparation method of the superconducting easily-dispersible graphene is characterized in that the acidic environment of the superconducting easily-dispersible graphene is at least one of hydrochloric acid, sulfuric acid, nitric acid, perchloric acid, hydroiodic acid and hydrobromic acid with the concentration of 5% -20%.

The conductive plastic disclosed by the invention is characterized in that the mass ratio of the addition amount of graphene in the conductive plastic is 0.05-5%.

The conductive plastic comprises at least one of polyethylene, polypropylene, polyvinyl chloride, polystyrene, polymethacrylate, polybutyl terephthalate and polycarbonate resin.

The invention relates to a conductive plastic, wherein the heating temperature of the plastic raw material is 70-250 ℃.

Has the advantages that:

according to the invention, the graphene powder obtained by modifying the graphene powder is good in dispersibility, has good fusibility with other materials, and is obviously improved in conductivity.

According to the invention, the modified graphene is added into the common plastic to obtain the conductive plastic with good electrical conductivity and thermal conductivity.

Drawings

Fig. 1 is a raman spectrum of untreated graphene and superconducting graphene powder.

Fig. 2 is a physical diagram of the conductive plastic prepared in the example.

Detailed Description

The embodiment of the invention provides a preparation method of superconducting easily-dispersible graphene powder and conductive plastic.

The medicine can be a reagent with analytical purity grade which is purchased in the market.

Example 1: preparation of superconducting easily-dispersible graphene powder

1) The graphene was washed with water 3 times to give a colorless transparent solution having a pH of about 7.

2) Dehydrating the washed graphene obtained in the step 1), and drying for 12 hours in vacuum at a low temperature of 50 ℃.

3) Weighing 1g of graphene obtained in the step 2), 1g of simethicone and 6g of water respectively, and soaking for 20min for later use after uniformly mixing.

4) Respectively weighing 5g of ethyl acetate, 2g of ethyl orthosilicate, 0.01g of formaldehyde and 100g of 10% hydrochloric acid solution, carrying out ultrasonic treatment for 20min, adding the graphene infiltrated in the step 3), carrying out ultrasonic treatment for 16h, washing with water until the pH value is 7, and carrying out ultrasonic treatment for 6h, dewatering and filtering.

5) Putting the graphene filter cake obtained in the step 4) into 100g of phosphoric acid solution with the concentration of 10% for ultrasonic dispersion, slowly dropping 10g of ammonium tungsten phosphate solution with the concentration of 20% in the ultrasonic dispersion process, performing ultrasonic treatment for 24 hours, dehydrating and cleaning until the pH value is 7, dropping 20g of rhenium phosphate solution with the concentration of 0.5%, continuing performing ultrasonic treatment for 6 hours, performing dehydration and freeze drying for 12 hours after cleaning to be neutral, and finally obtaining the superconducting easily-dispersed graphene powder.

A raman test is performed on graphene, as shown in fig. 1, raman spectra of untreated graphene and treated graphene are basically consistent, and the graphene powder prepared by the invention performs surface modification on graphene on the premise of not changing the essence of graphene.

And (3) respectively weighing untreated graphene with the same mass and the superconducting easily-dispersible graphene pressing sheet prepared in the example 1, wherein the thickness of a prepared sample is 0.15mm, and the resistivity of the sample sheet is tested. The resistivity of the untreated graphene was 24 Ω · cm^-1The resistivity of the superconductive easily-dispersed graphene is 0.125 omega-cm^-1The superconductivity prepared by the invention is easy to separateThe conductivity of the scattered graphene is obviously enhanced.

The method has the advantages that the graphene powder is dispersed in the aqueous solution, the maximum solubility of the untreated graphene powder is 5mg/ml, the maximum solubility of the superconducting easily-dispersed graphene prepared by the method is 15mg/ml, and the dispersibility of the graphene is greatly increased.

Example 2: preparation of electrically conductive plastics

Weighing 10g of polyethylene raw material, heating to 160 ℃ to enable the polyethylene to be in a molten state, adding 0.1g of the superconductive dispersible graphene powder prepared in the embodiment 1, uniformly stirring, and molding to obtain the conductive plastic prepared by the invention.

The prepared conductive plastic is shown in figure 2, and has a thickness of 0.2mm and a resistivity of 0.067 omega-cm^-1The thermal conductivity was 1.175W/m.K.

Finally, it is noted that the disclosed embodiments are intended to aid in further understanding of the invention, but those skilled in the art will appreciate that: various substitutions and modifications are possible without departing from the spirit and scope of the invention and the appended claims. Therefore, the invention should not be limited to the embodiments disclosed, but the scope of the invention is defined by the appended claims.