▎ 摘　　要

NOVELTY - A polylactic acid (PLA)/graphene nanosheet composite material contains 30-100 pts. wt. polylactic acid (PLA), 10-30 pts. wt. flame retardant, 5-10 pts. wt. flame retardant synergist, 1-5 pts. wt. nucleation accelerator, 2-6 pts. wt. toughening agent, 1-6 pts. wt. graphene nanosheet, 5-15 pts. wt. carbon fiber, 10-20 pts. wt. glass fiber, and 5-25 pts. wt. talcum powder in which graphene nanosheet specific surface area is 80-100 m2/g and is treated with silane coupling agent KH792 (RTM: N-2-(aminoethyl)-3-aminopropyltrimethoxysilane). USE - A polylactic acid/graphene nanosheet composite material (claimed). ADVANTAGE - Composite material has excellent flame retardant property, good toughness and high temperature properties, and high comprehensive mechanical strength, and preparation method improves compatibility of graphene nanosheet and PLA and makes graphene nanosheet fully dispersed in matrix resin. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of PLA/graphene nanosheet composite material which involves placing graphene nanosheet and silane coupling agent KH792 in dimethylformamide (DMF) solvent, mechanically stirring for 1-3 hours at rotation speed of 500-1500 rpm, uniformly mixing, putting in drying oven, controlling temperature at 45-55 degrees C, continuously drying for 1-6 hours to obtain surface-modified graphene nanosheet, uniformly mixing with polylactic acid, grinding in 3-roller grinder for 20-30 minutes, mixing with flame retardant, flame retardant synergist, toughening agent, nucleation accelerator, and talcum powder in high speed mixer for 10-30 minutes, placing in double-screw extruder hopper, adding carbon fiber and glass fiber in screw opening, melt blending and extruding at 170-220 degrees C temperature and 10-20 Hz main machine frequency, cooling extruded material, drying, and pelletizing.