▎ 摘　　要

NOVELTY - A heat-shrinkable polyester film comprises 60-90 pts. wt. dibasic acid component, 60-90 pts. wt. diol component, 15-30 pts. wt. elastomer, 0.01-1 pt. wt. silica and wear-resistant molding solution which comprises 30-40 pts. wt. graphene oxide, 250-300 pts. wt. Nafion (RTM: sulfonated tetrafluoroethylene-based fluoropolymer-copolymer) solution, 5-8 pts. wt. hydroxymethyl cellulose, 5-8 pts. wt. nickel acetate, 12-18 pts. wt. potassium borohydride, 8-15 pts. wt. cobalt acetate, 10-15 pts. wt. aluminum oxide and 3-5 pts. wt. phosphorus pentoxide. USE - Heat-shrinkable polyester film. ADVANTAGE - The heat-shrinkable polyester film is prevented from sudden decreasing in elongation at break in the non-main shrinkage direction. The method effectively prevents excessive filming induced by high temperature and high humidity environment, and improves stability of heat-shrinkable polyester film in elongation at break in non-main shrinkage direction. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method for producing heat-shrinkable polyester film, which involves (i) producing polyester film by mixing dibasic acid component, diol component and elastomer component, melt-extruding, and forming the melt into unstretched slabs through a die and chill roll, (ii) producing wear-resistant molding solution by adding nickel acetate, potassium borohydride, cobalt acetate, aluminum oxide and phosphorus pentoxide, mixing, and then placing in a vacuum oven for drying treatment, and placing in a muffle furnace for calcining at high temperature of 1400-1600 degrees C, and then placing the calcined material in a closed ball mill for ball milling, screening and transferring large particles of material into the ball mill again until passing the screening requirements of particle, mixing evenly, placing powdered substances in a smelting furnace, increasing the smelting temperature to 1600-1750 degrees C, stirring, and maintaining for 10-20 minutes until the temperature is dropped to 1400-1550 degrees C, then transferring into a closed ball mill for ball milling treatment, screening, and obtaining cemented carbide particles with particle size of 5-10 mesh, taking Nafion (RTM: sulfonated tetrafluoroethylene-based fluoropolymer-copolymer) solution with concentration of 5-15%, adding preset amount of graphene oxide powder with particle size of 30-40 mesh, and adding preset amount of hydroxymethyl cellulose, stirring at a speed of 150-300 rpm for 30 minutes and maintaining for 3-4 hours, (iv) injecting cemented carbide particles using high-pressure particle gun to Nafion (RTM: sulfonated tetrafluoroethylene-based fluoropolymer-copolymer) solution at a jet speed of 400 m/second, jetting specified mass of cemented carbide particles while stirring at a speed of 30-50 rpm in a mixer until the completion of the spray particles, and obtaining wear-resistant molding solution, (iii) stretching unstretched sheet in longitudinal direction and transverse direction at a constant draw ratio, and then carrying out heat-setting treatment at 150-180 degrees C, melting, and smearing wear-resistant molding solution in the surface, maintaining the temperature for 1-2 hours at room temperature and obtaining heat-shrinkable polyester film.