▎ 摘　　要

NOVELTY - Graphene platelet-filled composite film comprises carbon or graphitic matrix and 1-99% weight fraction of graphene platelets dispersed in the matrix. The graphene platelets are aligned along planar directions of the film and are e.g. pristine graphene, oxidized graphene and/or chemically functionalized graphene. The carbon or graphitic matrix is obtained by carbonizing a carbon precursor polymer at a carbonization temperature of at least 300 degrees C or by carbonizing and graphitizing the carbon precursor polymer at a final graphitization temperature higher than 1500 degrees C. USE - The film is useful as a heat-dissipating element in electronic device (claimed) or device housing. ADVANTAGE - The graphitic film: exhibits an inter-graphene spacing less than 0.337 nm and a mosaic spread value less than 1, degree of graphitization no less than 60% preferably 90% and/or a mosaic spread value less than 0.7, preferably less than 0.4 (all claimed); exhibits exceptionally high thermal conductivity, high electrical conductivity, and/or high mechanical strength and exhibits optical birefringence of less than 1.4 preferably less than 1.2; and is cost-effective. DETAILED DESCRIPTION - Graphene platelet-filled composite film comprises carbon or graphitic matrix and 1-99% weight fraction of graphene platelets dispersed in the matrix. The graphene platelets are aligned along planar directions of the film and are pristine graphene, oxidized graphene, reduced graphene oxide, fluorinated graphene, hydrogenated graphene, doped graphene and/or chemically functionalized graphene. The carbon or graphitic matrix is obtained by carbonizing a carbon precursor polymer at a carbonization temperature of at least 300 degrees C or by carbonizing and graphitizing the carbon precursor polymer at a final graphitization temperature higher than 1500 degrees C. The carbon precursor polymer is polyimide, polyamide, polyoxadiazole, polybenzoxazole, polybenzobisoxazole, polythiazole, polybenzothiazole, polybenzobisthiazole, poly(p-phenylene vinylene), polybenzimidazole and/or polybenzobisimidazole. The graphitic matrix comprises graphene layers, derived from the carbon precursor polymer, that are substantially oriented parallel to one another with an inclination angle between two graphene layers less than 5 degrees .