▎ 摘　　要

NOVELTY - A plastic cover material is prepared by laminating flame-retardant reinforced layer, foam layer and wear-resistant reinforced layer, and hot pressing. The flame-retardant reinforced layer is composed of 50-70 pts. wt. graphene/glass composite fiber, 5-10 pts. wt. polyvinylidene fluoride, 15-20 pts. wt. polyimide fiber, 30-40 pts. wt. aluminum hydroxide, 12-16 pts. wt. maleic anhydride grafted polyethylene, 2-4 pts. wt. silane coupling agent, 4-6 pts. wt. talc, and 10-15 pts. wt. flame retardant. The flame retardant comprises 4-8 pts. wt. sodium bicarbonate, 3-6 pts. wt. halloysite nanotubes, 0.5-2 pts. wt. titanium dioxide, and 1-3 pts. wt. pentaerythritol bisdimethylsilicate. The foam layer is composed of 80-100 pts. wt. PVC resin, 4-6 pts. wt. polypropylene foaming agent, 4-6 pts. wt. polyethylene octene co-elastomer, 4-6 pts. wt. pentaerythritol bisdimethylsilicate, 6-10 pts. wt. calcium stearate, 13-17 pts. wt. silane coupling agent, and 8-12 pts. wt. sodium bicarbonate. USE - Plastic cover material for cable trenches. ADVANTAGE - The plastic cover material has improved strength, impact resistance, bending resistance, mechanical properties and electrical conductivity, which eliminates the static electricity. DETAILED DESCRIPTION - A plastic cover material is prepared by laminating flame-retardant reinforced layer, foam layer and wear-resistant reinforced layer, and hot pressing. The flame-retardant reinforced layer is composed of 50-70 pts. wt. graphene/glass composite fiber, 5-10 pts. wt. polyvinylidene fluoride, 15-20 pts. wt. polyimide fiber, 30-40 pts. wt. aluminum hydroxide, 12-16 pts. wt. maleic anhydride grafted polyethylene, 2-4 pts. wt. silane coupling agent, 4-6 pts. wt. talc, and 10-15 pts. wt. flame retardant. The flame retardant comprises 4-8 pts. wt. sodium bicarbonate, 3-6 pts. wt. halloysite nanotubes, 0.5-2 pts. wt. titanium dioxide, and 1-3 pts. wt. pentaerythritol bisdimethylsilicate. The foam layer is composed of 80-100 pts. wt. PVC resin, 4-6 pts. wt. polypropylene foaming agent, 4-6 pts. wt. polyethylene octene co-elastomer, 4-6 pts. wt. pentaerythritol bisdimethylsilicate, 3-5 pts. wt. polyethylene glycol, 4-6 pts. wt. carboxymethyl cellulose, 18-22 pts. wt. talc, 6-10 pts. wt. calcium stearate, 13-17 pts. wt. silane coupling agent, and 8-12 pts. wt. sodium bicarbonate. The wear-resistant reinforced layer is composed of 40-50 pts. wt. graphene/glass composite fiber, 5-10 pts. wt. polyvinylidene fluoride, 25-30 pts. wt. polyethylene, 4-8 pts. wt. alumina, 8-12 pts. wt. copolymer of maleic anhydride and methyl acrylate, 2-4 pts. wt. maleic acid half ester, 1-3 pts. wt. acrylonitrile-styrene-butadiene copolymer, 1-3 pts. wt. p-phenylenediamine, 4-6 pts. wt. silane coupling agent, and 0.5-2 pts. wt. UV absorber. An INDEPENDENT CLAIM is included for preparation of plastic cover material, which involves putting raw materials of each layer into twin-screw extruder, pushing melt to screen changer, and then to distributor, passing material processed by distributor to mold, shaping in shaping table, transferring to cooling bracket for cooling by drawing device, transferring to slitting saw of slitting device, slitting by cross-cutting saw platform, moving out by conveying platform, and then laminating layers, and hot pressing.