▎ 摘　　要

NOVELTY - Thermally conductive composite material comprises polydimethylsiloxane (PDMS) and non-covalently modified graphene. The non-covalently modified graphene is modified with hyperbranched polyethylene copolymer with terminal branched polysilsesquioxane. USE - Thermally conductive composite material used as thermal interface materials (claimed). ADVANTAGE - The method adopts a hyperbranched polyethylene copolymer with terminal branched polysilsesquioxane to modify non-covalently modified graphene for improving the dispersion stability of graphene in chloroform or tetrahydrofuran. The introduction of a silicon-oxygen structure on the surface of graphene can significantly improve the compatibility of graphene and polydimethylsiloxane for improving the thermal conductivity of the flexible thermal conductive composite material and thermal conductivity can reach to 0.9 Watts per meter-Kelvin. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing thermally conductive composite material, which involves mixing non-covalently modified graphene in chloroform with polydimethylsiloxane, removing the solvent and curing to obtain desired thermally conductive composite material.