▎ 摘　　要

NOVELTY - Method for preparing graphene-modified nylon composite material, involves (i) dispersing graphene in mixed acid solution of concentrated sulfuric acid and concentrated nitric acid, ultrasonically processing for 12-24 hours, stirring and reacting at 50-80 degrees C for 6-8 hours, washing, filtering and drying to obtain graphene oxide, (ii) heat-treating graphene oxide obtained in step (i) at 400-800 degrees C under protection of inert gas for 1-2 hours to obtain heat-treated graphene oxide, (iii) dissolving heat-treated graphene oxide obtained in step (ii) and nylon 46 in formic acid, stirring, and ultrasonically processing to obtain mixed solution, where the amount of heat-treated graphene oxide is 0.1-2 %mass, (iv) placing mixed solution obtained in step (iii) in a reaction kettle at 1.5-2 MPa and 150-160 degrees C for 3-5 hours, releasing pressure and cooling to obtain mixed suspension, and (v) adding deionized water to mixed suspension obtained in step (iv), washing and drying. USE - The method is useful for preparing graphene-modified nylon composite material (claimed). ADVANTAGE - The method improves the compatibility problem between graphene and nylon, and improves tensile strength, bending strength and friction coefficient of the graphene-modified nylon composite material.