热塑性电力电缆绝缘材料:历史与发展

Thermoplastic Insulation Materials for Power Cables: History and Progress

交联聚乙烯（XLPE）具有优异的机械、热力学及绝缘性能,被广泛用作电力电缆绝缘材料。然而,XLPE是热固性塑料,电缆退役后绝缘难以循环再利用。另外,XLPE生产过程产生的副产物也会影响电缆的性能,不利于工人的健康。以上因素都是推动发展热塑性电缆绝缘的动力。本文介绍了电力电缆对绝缘材料电气特性的基本要求,总结了低密度聚乙烯（LDPE）、高密度聚乙烯（HDPE）及聚丙烯（PP）等有可能用作热塑性电缆绝缘的三类聚合物的结构与电气特性的关系。并重点综述了聚合技术、共聚技术、共混技术、添加剂、纳米添加、化学改性等在调控上述三类热塑性绝缘材料结构与性能方面的研究进展。最后,从电缆绝缘材料结构与性能关系、聚合物存在多样性结构以及聚合物合成新技术日新月异等方面,对未来热塑性电力电缆绝缘材料的发展进行了展望。分析认为：新型合成技术是实现高性能热塑性电力电缆绝缘材料的有力手段;复合、改性技术则是发展热塑性电力电缆绝缘材料的重要补充。

Power cables insulated by cross-linked polyethylene（XLPE） have been widely used in power transmission and distribution because of the excellent mechanical, thermal and dielectric properties of the insulation. However, the thermoset nature results in super low recycling capability of XLPE insulation out of service. In addition, the byproducts of cross-linking also lead to negative influence on the cable properties and health of workers. These factors call for and drive the development of thermoplastic cable insulation. We introduced the basic requirements of electrical properties of power cable insulation and summarized the structure-property relationship of low density of polyethylene（LDPE）, high density of polyethylene（HDPE） and polypropylene（PP）, which can be possibly used as thermoplastic cable insulation. Emphasis was given on the roles of polymerization, copolymerization, blending, additives, nanoparticles and chemical modification in tailoring the structure and property of thermoplastic insulating materials. Finally, the perspectives on the development of thermoplastic insulation materials were presented from the viewpoints of structure-property relationship of power cable insulation, multi-structure of the same type of polymer, and the rapid development of the polymerization techniques of polymers. It is suggested that the new polymerization techniques are the powerful strategy for realizing the high performance of thermoplastic power cable insulating materials, and the strategies of composite and modification are also important supplements.