▎ 摘　　要

NOVELTY - Lightweight high thermal conductivity polymer composite material comprises polymers, layered graphite fillers and spherical fillers, where the spherical fillers are adiabatic hollow and rigid spherical hollow glass microspheres, hollow silica, hollow calcium carbonate, which are blend. The content of the layered graphite filler and the spherical filler in the polymer composite material is 30-70 wt.%, and the content of the spherical filler in the polymer composite material is 1-10 wt.%. USE - The lightweight high thermal conductivity polymer composite material is useful in plastic product (claimed). ADVANTAGE - The method: does not add compatibilizer, under the condition of antioxidant, using a certain amount of spherical filler of insulating hollow and rigid sphere to change the orientation of the graphite in the polymer matrix, which improves the thermal conductivity of the polymer composite material; can reduce the density and conductivity; improves the mechanical property; improves the smooth fine degree and surface hardness of the surface to prepare light weight, high heat-conducting and high surface smoothness of the product. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method for preparing sheet by using the light high heat-conducting polymer composite material comprising (1) vacuum drying the polymer, layered graphite filler and spherical filler at 80degrees Celsius for 12-24 hours, (2) adding the dried polymer, layered graphite filler and spherical filler into melting and mixing device, melting and mixing at 180-300degrees Celsius to obtain uniform and stable blend, (3) discharging the blend from the melting and mixing device, cooling to normal temperature to obtain the polymer composite material, and (4) hot pressing the polymer composite material firstly into sheet in the molten state, and cold pressing to obtain the sheet with thickness of 100-1000 mm.