无机填料填充PE-LD/EVA合金的导热及阻燃性能

采用氧化铝（Al2O3）为导热填料、氢氧化镁［Mg(OH)2］为阻燃填料，以低密度聚乙烯（PE-LD）和乙烯醋酸乙烯共聚物（EVA）为基体树脂制备导热阻燃复合材料。通过导热性能测试、燃烧行为表征（极限氧指数和垂直燃烧测试）以及热重分析研究了PE LD/EVA/Al2O3/Mg(OH)2复合材料的导热性能、阻燃性能及热稳定性。结果表明，含有50份Al2O3及50份Mg(OH)2的复合材料，在PE-LD/EVA质量比为1/1时，热导率可达到1.21 W/m·K；材料的阻燃性能及热稳定性都随 EVA 含量的增加而增大，极限氧指数从27.0 % 提高到31.5 %，UL 94 垂直燃烧从无等级提高到V-0级，残炭率从46.5 %提高到57.7 %。

Thermal Conductivity and Fire Resistance of PE-LD/EVA Blends Filled with Inorganic Fillers

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 ℃.