Abstract: The composites of PE-HD/graphite/toughening master batch were prepared using a twin-screw extruder. The effects of size and content of graphite, and surface treatment on thermal conductivity and mechanical properties of the composites were investigated. It indicated that the graphite was best treated with titanium acid grease NDZ201. The smaller the particle size of graphite, the larger the thermal conductivity and mechanical properties. CaCO3 toughening master batch could increase the thermal conductivity and mechanical properties of the composites. When the mass ratio of PE-HD/graphite/250B was 45/30/25, the thermal conductivity of the composite was 1.72 W/(m·K), the impact strength was similar to neat PE-HD, the tensile strength and flexural strength of the composites increased by 52 % and 88 %, respectively.

Key words: high density polyethylene, graphite, toughening master batch, thermal conductivit, mechanical property