▎ 摘　　要

NOVELTY - High-strength flame-retardant polyvinyl chloride sheath comprises reinforcement layer, main body and flame retardant layer. The main body comprises 40-55% polyvinyl chloride particles, 30-36% graphene, 15-20% light calcium carbonate, 6-8% antioxidant, 4-6% plasticizer, and 2-3% stabilizer. The preparation of polyvinyl chloride sheath comprises (i) placing the above-mentioned raw materials into a stirring device and sieving to 50 mesh, (ii) placing the mixed materials into the mixing device again, completely mixing, and placing the product in the heating furnace to preheat to 200-300 degrees C, and (iii) heating the furnace to increase the temperature of the melting cellar to about 300-400 degrees C to ensure that all the body materials can be fully mixed and stirred, promoting the full mixing of the molecules between the ingredients for 2-3 hours, and turning the heating furnace on to cool the completed body mixture. USE - Used as high-strength flame-retardant polyvinyl chloride sheath. ADVANTAGE - The polyvinyl chloride sheath improves the firmness of the sheathing tube, improves the strength and toughness of the PVC sheathing tube, prolongs the service life of the entire sheath tube, and increases its friction index and increase the external friction effect. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing the polyvinyl chloride sheath, comprising (i) keeping the temperature of the prepared body raw material at about 120 degrees C, placing the raw material into the twin-screw extruder, completely mixing, adding reinforcement layer into the raw material, and placing for extrusion and granulation; (ii) cooling and forming the extruded PVC sheathing tube, and uniformly coating the surface layer of the PVC jacket with a brush with a uniformly stirred flame-retardant layer raw material, uniformly coating a layer of about 0.2 mm, using UV lamps to cure and irradiate, waiting for the curing to stabilize, coating a layer of about 0.4 mm uniformly to perform secondary curing; and (iii) cooling and packing the cured PVC sheath.