UHMWPE/LLDPE/BN复合塑料导热性能研究

THERMAL CONDUCTION PROPERTY OF UHMWPE/LLDPE/BN COMPOSITE PLASTICS

将氮化硼(BN)粒子和超高分子量聚乙烯/线性低密度聚乙烯(UHMWPE/LLDPE)分别用熔融辊炼法和粉末混合法制备导热聚乙烯塑料。研究了制备方式、填料含量及偶联剂对填料分散状态及体系热导率、热阻的影响。研究结果表明,粉末法制备的塑料由于BN的高分散效果使得体系的导热性能明显高于熔融辊炼法制备的体系,热导率随填料含量而增加,偶联剂处理有利于提高塑料的热导率。在UHMWPE/LLDPE/BN中添加少量氧化铝短纤维有助于提高体系的力学强度、韧性及热导率。

A novel thermal conductive composite plastic was prepared using boron nitride（BN） as filler, and linear low-den- sity polyethylene/ultrahigh molecular weight polyethylene（LLDPE/UHMWPE） blend as matrix by a powder mixture and a roll-milled mixture, respectively. The effects of the processing way, the concentration and surface treatment of BN on thermal conductivity and thermal resistance of the composites were investigated. It was found that the composites obtained from a powder mixture exhibited an obviously higher thermal conductivity owing to the desired dispersion of filler, compared to that from a roll-milled mixture. Thermal conductivity of the composites increased with increasing BN content. Also, the composite thermal conductivity was further enhanced by using silane coupling agent. Alumina short fiber was then added to improve the overall composite toughness, strength and thermal con- ductivity of the composites.