▎ 摘　　要

NOVELTY - Self-repairing dielectric composite material comprises self-repairing linear polyurethane, multi-walled carbon nanotubes, graphene oxide and N,N-dimethylformamide. USE - Used as self-repairing dielectric composite material. ADVANTAGE - The self-repairing dielectric composite material has good mechanical performance, high dielectric constant and low dielectric loss and can achieve high-efficiency self-repair while heating after mechanical damage. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing dielectric composite material, comprising (i) dissolving 4,4'-methylenebis(phenyl isocyanate) and polytetrahydrofuran in N,N-dimethylformamide solvent to obtain 4,4'-methylenebis(phenylisocyanate) solution and polytetrahydrofuran solution; (ii) reacting 4,4'-methylenebis(phenyl isocyanate) solution and polytetrahydrofuran solution under inert gas protection; (iii) dissolving bis(4-hydroxyphenyl)disulfide in N,N-dimethylformamide solvent to obtain bis(4-hydroxyphenyl) disulfide solution, adding bis (4-hydroxyphenyl) disulfide solution to reactant obtained in step (ii) to obtain self-repairing linear polyurethane; (iv) dispersing multi-walled carbon nanotubes and graphene oxide respectively in N,N-dimethylformamide solvent to form multi-walled carbon nanotube suspension and graphene oxide suspension respectively; (v) mixing multi-walled carbon nanotube suspension and graphene oxide suspension, dispersing mixture by ultrasonic waves, and adding to self-repaired linear polyurethane for melt blending; (vi) adding reducing agent to system after melt blending in step (v), adding solvent to the system and drying to obtain reaction product; (vii) dissolving reaction product in N,N-dimethylformamide solvent to obtain reaction product solution; and (viii) pouring reaction product solution into a template and removing solvent in reaction product solution.