▎ 摘　　要

NOVELTY - High-smooth and heat-insulating polyimide film, comprises 40-60 wt.% polyamic acid, 20-25 wt.% distilled water, 10-15 wt.% organic polymer solvent, 5-10 wt.% dispersant, 5-10 wt.% polyamide resin, 2-5 wt.% polyethylene wax, 2-5 wt.% high-melting point wax, 2-5 wt.% maleic anhydride-grafted copolymer wax, 2-5 wt.% polyethylene, 2-5 wt.% polyisobutylene, 2-5 wt.% higher fatty alcohol, 3-5 wt.% graphene powder, 3-5 wt.% silicon dioxide powder, and 3-5 wt.% calcium carbonate powder. USE - The high-smooth and heat insulating polyimide film is useful for motors (claimed). ADVANTAGE - The polyimide film improves brightness, smoothness, and glossiness of surface. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing high-smooth and heat insulating polyimide film, comprising (i) adding polyamic acid, distilled water and organic polymer solvent into dissolution barrel, stirring the dissolution barrel at a rotating speed of 200-300 revolution per minute, and continuously stirring for 5-10 minutes to obtain polyamic acid solution, (ii) adding prepared polyamic acid solution into reaction vessel, slowly adding dispersant and polyamide resin into reaction vessel uniformly, stirring the reaction vessel at a rotating speed of 500-800 revolution per minute, heating in the reaction vessel to 220-250 ℃, continuously stirring for 10-20 minutes, stopping heating, then slowly adding polyethylene, polyisobutylene and higher fatty alcohol into the reaction vessel, continuously stirring in the reaction vessel at a rotating speed of 1000-1200 revolution per minute for 5-10 minutes, and stopping stirring, (iii) taking out the mixture in the reaction vessel, placing it into mixing tank, sieving the graphene powder, silicon dioxide powder and calcium carbonate powder using 60-80 meshes of screen, placing the screened powder into mixing tank, stirring at a rotating speed of 800-1000 revolution per minute, continuously stirring for 5-8 minutes, adding polyethylene wax, high-melting point wax and maleic anhydride copolymer wax into mixing tank, heating the mixing tank to 150-200 ℃, then stirring the mixing tank at a rotating speed of 300-500 revolution per minute, continuously stirring for 10-13 minutes, stopping heating, stirring, allowing to stand for 6-12 hours in the mixing tank and cooling to room temperature, and (iv) taking out the mixed solution in the mixing tank, coating the mixed solution on glass sheet, then placing the glass sheet coated with mixed solution on the adhesive homogenizing machine, rotating the glass sheet at a rotating speed of 1500-2000 revolution per minute, covering the mixed solution uniformly on the glass sheet, then allowing to stand the glass sheet for 30-60 minutes until the mixed solution is solidified to obtain uniformly distributed adhesive film, then placing the adhesive film into drying box, drying at 100-160 ℃ for 15-25 minutes, heating the adhesive film, and performing cyclization reaction of polyamic acid to obtain polyimide film.