聚苯乙烯接枝共聚物/低密度聚乙烯的介电性能  

Dielectric Properties of Polystyrene Graft Copolymer/Low Density Polyethylene

作　　者：闫涵 宋淑伟 赵洪[1] 姚占海[2] YAN Han;SONG Shuwei;ZHAO Hong;YAO Zhanhai(Key Lab of Engineering Dielectrics and Their Application,Ministry of Education,Harbin University of Science and Technology, Harbin 150080,China;Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China)

机构地区：[1]哈尔滨理工大学工程电介质及其应用教育部重点实验室,哈尔滨150080 [2]中国科学院长春应用化学研究所,长春130022

出　　处：《高电压技术》2018年第12期3840-3847,共8页High Voltage Engineering

基　　金：国家自然科学基金重点项目(51337002);黑龙江省普通本科高等学校青年创新人才培养计划(UNPYSCT-2016158)~~

摘　　要：为了探索解决低密度聚乙烯在高温环境下耐电性能大幅下降问题的方法,通过电子辐照与乳液聚合方法将聚苯乙烯分子接枝到聚乙烯分子链上,制备了不同组分聚苯乙烯接枝共聚物/低密度聚乙烯复合材料。当聚苯乙烯质量分数为6%时,复合材料在80-90℃下交流耐电性能较纯低密度聚乙烯提升约20%。差示扫描量热法、动态力学分析测试等试验结果显示:含6%聚苯乙烯的复合材料与纯低密度聚乙烯相比结晶度提高了10%;室温下复合材料的拉伸屈服应力和断裂伸长率均有提高;存储模量在85℃下提高至70MPa。复合材料交流击穿电场强度提升应与两种因素有关:1)接枝聚苯乙烯使复合材料弹性模量增大,抵御电破坏能力增强;2)复合材料内部聚苯乙烯苯环结构可以捕获热电子,耗损热电子能量,具有一定抑制电子崩产生的作用。To explore methods for solving the problem that the dielectric properties of low density polyethylene sharply decrease at high temperatures, the polystyrene molecule is grafted onto polyethylene chain by electron irradiation and emulsion polymerization, and the PS-g-LDPE/LDPE composite material of different components is prepared. The AC breakdown strength of composite with 6% polystyrene improves by 20% within temperature span from 80 ℃ to 90 ℃ comparing with pure LDPE. The results from differential scanning calorimetry and dynamic mechanical analysis tests show that the crystallinity of the composite with 6% polystyrene increases by 10%; at room temperature, the tensile yield stress and elongation of the composite increase; the storage modulus of the composite material at 85 ℃ reaches 70 MPa. Two main reasons for the obvious improvement of the AC breakdown strength are as follows: 1) the addition of polystyrene increases the elasticity modulus of composite material, enhancing the ability to resist electrical damage. 2) the benzene ring in polystyrene can serve as trapping sites in the composite to constrain the hot electron and consume its energy, which can inhibit the generation of electron-avalanche.

关 键 词：聚苯乙烯 低密度聚乙烯 电介质复合材料 介电性能 悬浮接枝 

分 类 号：TM21[一般工业技术—材料科学与工程]