Preparation method of tough graphene/cellulose composite heat-conductive and electro-conductive film

Abstract

The invention discloses a preparation method of a tough graphene / cellulose composite heat-conductive and electro-conductive film. The preparation method of the tough graphene / cellulose composite heat-conductive and electro-conductive film comprises the following steps: firstly, dispersing the wood pulp into an aqueous solution to peel the wood pulp into single nano diameter single fibrous bundles under the action of liquid shear force; diluting the single fibrous bundles with deionized water and obtaining the low concentration cellulose aqueous solution through treating by a high-speed shearing machine for a certain period of time; then dispersing the industrial graphene nanosheets evenly into the aqueous solution containing the dispersant through ultrasonic treatment; then dripping the prepared cellulose aqueous solution gradually into the graphene dispersion; and preparing the graphene / cellulose composite film through ultrasonic mixing, suction filtration, drying and other processes. The obtained film has good flexibility, thermal conductivity and electrical conductivity, and the mechanical, thermal and electrical properties of the film can be further improved through hot pressing treatment. The preparation method of the tough graphene / cellulose composite heat-conductive and electro-conductive film has the advantages of simple process, low cost, green environment protection and wide application value in the field of functional composite materials.

Description

technical field [0001] The invention belongs to the research field of nanomaterials and functional materials, and specifically relates to a preparation method of a tough graphene / cellulose composite heat-conducting and conducting film. Background technique [0002] Graphene refers to a single-layer carbon carbon material with a thickness of about 0.35 nm, which is closely arranged in a hexagonal two-dimensional honeycomb lattice of carbon atoms. Carbon atoms in graphene are connected to three adjacent carbon atoms through α bonds, and the bond length between carbon and carbon is only 0.142 nm. These strong C-C bonds form a bond angle of 120°, making graphene the world’s most The strongest and hardest material in the world. The specific surface area of ​​graphene is as high as 2630 m 2 / g, the tensile strength and Young's modulus reach 130GPa and 1TPa respectively, and its theoretical thermal conductivity is 5300 W / m K, which is much higher than that of metal and carbon nan...

AI Technical Summary

Problems solved by technology

[0003] At present, most of the graphene film preparation is single-layer graphene. For example, the graphene film prepared by CVD method is mainly single-layer graphene. This method is limited by the disadvantages of complex process, harsh conditions, low yield and high cost. Large-scale industrial application of graphene

Another example is the use of chemical redox method to prepare graphene oxide, obtain graphene oxide film by vacuum filtration, and then obtain graphene film by chemical reduction method. The strong oxidizing agent used in the chemical stripping process of this method usually destroys carbon. The planar structure of atoms produces defects, which reduce the thermal and electrical conductivity of graphene

Generally speaking, the preparation cost of single-layer graphene is relatively high, and the technology is not yet mature, so it is difficult to realize large-scale application in the field of composite materials.

Images