导热绝缘PE-LD/PE-g-MAH/h-BN泡沫塑料的制备及性能研究

采用熔融共混法制备了一系列导热绝缘的低密度聚乙烯/马来酸酐接枝聚乙烯/六方氮化硼(PE-LD/PE-g-MAH/h-BN新型泡沫塑料，研究了相容剂PE-g-MAH的加入、h-BN含量对PE-LD/PE-g-MAH/h-BN泡沫体系导热性能、绝缘性能、力学性能及热稳定性的影响。结果表明，PE-g-MAH有利于增加PE?LD与h?BN的界面黏结，增强泡沫体系拉伸强度和断裂伸长率，显著提高其热导性能；当h-BN含量为30 %时， PE-LD/PE-g-MAH/h-BN泡沫体系的导热率为0.256 W/(m·K)，相对于PE-LD/h-BN泡沫体系的0.217 W/(m·K) 和纯PE-LD泡沫体系的0.039 W/(m·K)，热导率分别提高1.18和6.57倍，同时保持较好的绝缘性和热稳性。

Preparation and Properties of Thermally Conductive Insulating PE-LD/PE-g-MAH/h-BN Foamed Plastics

A series of heat conductive and insulating foams were prepared by melt blending using low?density polyethylene (PE-LD), maleic anhydride-grafted polyethylene (PE-g-MAH) and boron nitride (h-BN) as raw materials. The effects of PE-g-MAH and h-BN on the thermal conductivity, insulation, mechanical properties and thermal stability of PE-LD/PE-g-MAH/h-BN foams were investigated. The result indicated that the foams achieved an improvement in elongation at break and tensile strength, and their thermal conductivity was also enhanced significantly due to the strong interaction between PE-LD and h-BN bridged by PE-g-MAH. The foams gained a thermal conductivity of 0.256 W/（m·K） at the h-BN content of 30 wt%, and their thermal conductivity increased by 118 % and 657 % compared to PE-LD/h-BN foam and pure PE-LD foam, respectively. Moreover, the PE-LD/PE-g-MAH /h-BN foams obtained good insulation and thermal stability.