▎ 摘　　要

NOVELTY - Polyimide film with improved thermal conductivity, comprises a diamine monomer, dianhydride monomer, imidization solution, graphene, dehydrating agent, catalyst, rare earth oxide and aluminium nitride, where the thickness of the polyimide film is 40-60 m, the elongation at break is 70-130 %, the elastic modulus is 2.7-4 GPa and the coefficient of thermal expansion is 16-32 parts/million/K. USE - Used as polyimide film with improved thermal conductivity. ADVANTAGE - The film reduces the dielectric loss of the polyimide film; improves the heat conducting performance of the polyimide film; wraps the semi-quantity of the heat conducting slurry on the surface of the polyimide film; and can process secondary processing to the polyimide film with unqualified quality, the product percent of pass is 100 %, which avoids the occurrence of unqualified product. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing polyimide film with improved thermal conductivity comprises (i) mixing the rare earth oxide, graphene, aluminium nitride according to a certain proportion, adding into ball mill for grinding and sieving in the inert gas environment, sintering for 2-3 hours at the temperature of 1900-2000degrees Celsius to obtain the mixture; (ii) adding the diamine monomer and dianhydride monomer into the solvent, mixing and stirring at -20-0degrees Celsius to obtain the mixed solution A, where the viscosity of the mixed solution A is not less than 100000 centipoises; (iii) dispersing the mixture in an organic solvent to form a heat-conducting slurry B; (iv) stirring and 1.5-3 H the mixed solution A with the imidization solution, and adding one of the two parts of heat-conducting slurry B to obtain the intermediate of the polyimide film; (v) adding the dehydrating agent and catalyst into the polyimide film intermediate; (vi) mixing and stirring in inert gas at -20-0degrees Celsius to obtain the polyimide film mixed solution; (vii) defoaming the polyimide film mixed solution, filling, forming film, drying and peeling to obtain the polyimide film pre-finished product; (viii) uniformly and fully wrapping the remaining half of the heat conducting slurry B on the polyimide film pre-finished product, and leading to the imidization furnace for hot pressing amination.