Abstract: Aluminum oxide (Al2O3) and magnesium hydroxide ［Mg(OH)2］ were introduced into low density polyethylene/ethylenevinyl acetate copolymer (PE-LD/EVA) to improve the thermal conductivity and flame retardancy. Thermal conductivity test, limiting oxygen index, UL94 test and thermal gravimetric analysis were used to characterize the thermal conductivity, flammability, and thermal behavior of PE-LD/EVA/Al2O3/Mg(OH)2 composites. The results showed that the thermal conductivity reached 1.21 W/m·K at the presence of 50 phr Al2O3 and 50 phr Mg(OH)2 and the PE-LD/EVA mass ratio of 1/1; the introduction of EVA into composites apparently increased the limited oxygen index from 27.0 % to 31.5 % , and the UL 94 level was improved from no rating to V-0, the residual char increased from 46.5 % to 57.7 % in TG at 800 ℃.

Key words: low density polyethylene, ethylene-vinyl-acetate copolymer, thermal conductivity, flame retardant, selective distribution