▎ 摘　　要

NOVELTY - Fiber-reinforced high density polyethylene/graphene composite material comprises 15-60 pts. wt. natural plant fiber, 0.5-2 pts. wt. graphite, 40-60 pts. wt. polyolefin, 1-10 pts. wt. foaming agent, 0.5-1 pts. wt. crosslinking agent, 5-8 pts. wt. plasticizer, 1-10 pts. wt. lubricant, 1-10 pts. wt. activating agent. USE - Used as fiber-reinforced high density polyethylene/graphene composite material. ADVANTAGE - The composite material: has excellent processing performance, physical and mechanical performance, high strength, excellent toughness and increased thermal conductivity; and solves the problem of compatibility between natural plant with polyolefin. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing composite material, comprising (i) washing surface of natural plant fiber repeatedly to with deionized water remove impurities, placing into a constant temperature oven, drying at 85-90 degrees C for 3-6 hours, adding 3-5 g the dried natural plant fiber into 100 ml polytetrafluoroethylene lined hydrothermal reactor, adding 70 ml strong alkali solution having a concentration of 1.5-2.5 mol/l, placing in a constant temperature oven, drying at 170-190 degrees C for 10-12 hours, cooling naturally, washing solid matter with deionized water until reaches to neutral, then placing constant temperature blast oven, and drying at 70-80 degrees C for 10-12 hours to obtain white flocculent precursor, (ii) adding low density polyethylene powder into p-xylene solvent, then heating to 80-100 degrees C in water bath, and dissolving completely the powder under stirring condition to obtain 2-5 wt.% low density polyethylene solution, (iii) cooling to 60-80 degrees C, adding the natural plant fiber and graphene oxide into the low-density polyethylene solution and soaking for 30-50 minutes, taking out, then placing in an oven, and drying at 110-120 degrees C for 7-9 hours, (iv) adding polyolefin, foaming agent, activating agent, crosslinking agent, plasticizer and lubricant into a mixer, and mixing for 15-25 minutes at a stirring speed of 800-1000 revolutions/minute, (v) adding resulting mixture obtained in step (iv) into a flat vulcanizing machine, then pressure molding at molding temperature of 150-180 degrees C for 10-15 minutes under a pressure of 5-15 MPa to obtain polyolefin sheet, and (vi) adding the treated natural plant fiber fabric obtained in step (iii) and the polyolefin sheet into a mold, pressure molding in flat vulcanizing machine to obtain final product, where the molding temperature is 150-180 degrees C, the pressure is 5-15 MPa, and the time is 10-15 minutes.