▎ 摘　　要

NOVELTY - Composite foamed sheet comprises 40-50 pts. wt. polyvinyl chloride (PVC), 20-30 pts. wt. acrylonitrile butadiene rubber (NBR), 8-10 pts. wt. nano-hydroxyapatite, 8-10 pts. wt. liquid silicone rubber, 3-5 pts. wt. oxidized polyethylene wax, 1-2 pts. wt. graphene oxide, 1-2 pts. wt. white carbon black, 2-5 pts. wt. AC foaming agent, 1-2 pts. wt. triethyl borate, 0.5-1 pts. wt. light stabilizer, 4-5 pts. wt. calcium-zinc stabilizer, 0.4-0.5 pts. wt. accelerant tetramethylthiuram disulfide (TMTD) and 0.5-1 pts. wt. stearic acid. USE - Composite foamed sheet. ADVANTAGE - The composite foamed sheet has effectively enhanced heat resistance, mechanical properties, strength, mobility, flame retardance, and environmental protection, and has prominent application prospects in multiple building material field. DETAILED DESCRIPTION - Composite foamed sheet comprises 40-50 pts. wt. polyvinyl chloride (PVC), 20-30 pts. wt. acrylonitrile butadiene rubber (NBR), 8-10 pts. wt. nano-hydroxyapatite, 8-10 pts. wt. liquid silicone rubber, 3-5 pts. wt. oxidized polyethylene wax, 1-2 pts. wt. graphene oxide, 1-2 pts. wt. white carbon black, 2-5 pts. wt. AC foaming agent, 1-2 pts. wt. triethyl borate, 0.5-1 pts. wt. light stabilizer, 4-5 pts. wt. calcium-zinc stabilizer, 0.4-0.5 pts. wt. accelerant tetramethylthiuram disulfide (TMTD), 0.5-1 pts. wt. stearic acid, 1-1.5 pts. wt. vulcanizing agent phenyl-modified polydimethylsiloxane (PDM), 5-8 pts. wt. epoxy fatty acid methyl ester, 2-4 pts. wt. zinc methacrylate, 0.1-0.2 pts. wt. sodium lignosulfonate and 20-30 pts. wt. deionized water. An INDEPENDENT CLAIM is included for a method for preparing composite foamed sheet, which involves: (A) adding sodium lignosulfonate into deionized water, stirring for complete dissolution, adding nano-hydroxyapatite and graphene oxide, mixing, grinding for 20-30 minutes and drying to obtain mixed material; (B) mixing NBR and liquid silicone rubber uniformly in a mixer at a temperature of 160 degrees C for 20-30 minutes, adding PVC, oxidized polyethylene wax, white carbon black, epoxy fatty acid methyl ester, light stabilizer, calcium-zinc stabilizer, zinc methacrylate and the obtained mixed material, condensing continuously for 30-50 minutes to obtain composite base, and the cooling the base material naturally cooled to room temperature; (C) adding the prepared base material and other remaining components into a rubber mixing machine, mixing at a temperature of 50 degrees C for 20-30 minutes, and passaging three times before discharging to form a sheet; and (D) subjecting the sheet to hot-pressing at a temperature of 170-175 degrees C and 12-16 mega Pascals in a mold for 15-20 minutes, and cooling to obtain composite foamed sheet.