▎ 摘　　要

NOVELTY - A composite material comprises 50-100 pts. wt. polylactic acid, 4-10 pts. wt. chitosan, 2-8 pts. wt. graphene nanosheet, 5-14 pts. wt. carbon fiber, 8-14 pts. wt. glass fiber, 5-10 pts. wt. calcined kaolin, 1-5 pts. wt. silica sol, 1-5 pts. wt. diaminodiphenylmethane tetraglycidylamine and 1-3 pts. wt. silane coupling agent. The graphene nanosheet has a specific surface area of 80-100 m2/g and is treated with diaminodiphenylmethane tetraglycidylamine. USE - Composite material. ADVANTAGE - The composite material has excellent high-temperature resistance and comprehensive mechanical strength and high toughness. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for the method for preparing the composite material, which involves adding graphene nanosheet to dimethylformamide together with diaminodiphenylmethane tetraglycidylamine, mechanically stirring at 500-1500 rpm for 1-3 hours, uniformly mixing, drying the mixture in a drying oven at 45-55 degrees C for 6 hours to obtain surface-modified graphene nanosheets, uniformly mixing the surface-modified graphene nanosheets with polylactic acid particles, grinding in a three-roller grinding machine for 20-30 minutes to obtain a polylactic acid graphene mixture, mixing polylactic acid graphene mixture, chitosan, calcined kaolin, silane coupling agent, silica sol and diaminodiphenylmethane tetraglycidylamine in a high-speed mixer, uniformly mixing for 10-30 minutes, adding the uniformly-mixed mixture to a hopper of a twin-screw extruder, adding carbon fibers and the glass fibers to a fiber feeding port of the twin-screw extruder, subjecting the mixture to melt blending extrusion, cooling the extruded materials, carrying out blow-drying and cutting to obtain the composite material.