▎ 摘　　要

NOVELTY - Vertically oriented three-dimensional expanded graphite heat conductor comprises sheet-shaped expanded graphite and reduced graphene oxide. The sheet-shaped expanded graphite and reduced graphene oxide are vertically arranged in the vertically oriented three-dimensional expanded graphite heat conducting body. The vertically oriented three-dimensional expanded graphite heat conductor is a three-dimensional structure. USE - The vertically oriented three-dimensional expanded graphite thermal conductor is used as a thermally conductive reinforcing filler in a thermally conductive polymer-based composite material (claimed). ADVANTAGE - The method improve the thermal conductivity of polymer matrix composites. The longitudinal thermal conductivity of the thermally conductive polymer-based composite material can reach 10-40 W/(m.K). DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for (1) Preparing comprising (i) introducing exfoliated graphite to the graphene oxide aqueous slurry under mechanical stirring to obtain an expanded graphite-graphene oxide mixed slurry, (ii) mixing expanded graphite-graphene oxide, subjecting mixed aqueous slurry of graphene to directional freezing treatment, and freeze-drying to obtain a vertically oriented expanded graphite-graphene oxide hybrid material, (iii) subjecting expanded graphite-graphene oxide hybrid material into a high-temperature reduction treatment in a nitrogen atmosphere to obtain a vertically oriented expanded graphite-graphene oxide hybrid material, oriented three-dimensional expanded graphite thermal conductor; where the expanded graphite-graphene oxide mixed slurry described in step (i) does not contain surfactant components; expanded graphite and graphene oxide pass through polarities such as hydroxyl groups and carboxyl groups on the surface of graphene oxide group connection. (2) Filler which is vertically oriented three-dimensional expanded graphite heat conductor. (3) thermally conductive polymer composite material comprises vertically oriented three-dimensional expanded graphite thermal conductor as a filler and a polymer matrix.