直流电容器专用聚丙烯树脂的结构与性能研究  

Research on structure and performance of polypropylene resin for DC capacitors

作　　者：苏尧天 张翀 张兴辉 郭少玮 刘炬阳 邢照亮 SU Yaotian;ZHANG Chong;ZHANG Xinghui;GUO Shaowei;LIU Juyang;XING Zhaoliang(State Key Laboratory of Advanced Power Transmission Technology,China Electric Power Reserch Institute,Beijing 102209,China;State Grid Corporation of China,Beijing 100032,China)

机构地区：[1]中国电力科学研究院有限公司先进输电技术国家重点实验室,北京102209 [2]国家电网有限公司,北京100032

出　　处：《绝缘材料》2025年第4期37-44,共8页Insulating Materials

基　　金：国家电网公司科技项目(5500-202255488A-2-0-KJ)。

摘　　要：本文采用高温液体核磁(^(13)CNMR)、凝胶渗透色谱(GPC)、差示扫描量热(DSC)法研究国内外3种不同耐温等级的直流电容器专用聚丙烯树脂,分析材料微观结构对电学性能的影响。结果表明:等规指数、分子链间缺陷分布和分子量特征共同影响聚丙烯的结晶特性,进而影响材料最终的高温介电性能。进口聚丙烯树脂的5单元等规指数大于97%,分子链间立构缺陷分布窄(I=1.075),重均分子量较高且分子量分布指数较大(PDI>5.6),表现出优异的高温绝缘性能(电气强度α=533 kV/mm)。而国产聚丙烯树脂的分子量分布窄(PDI<5),重均分子量较低,5单元等规指数小于97%以及分子链间立构缺陷分布较宽(I=1.106),进而导致其高温绝缘性能较差,电气强度较低(α=497 kV/mm)。High temperature liquid nuclear magnetic resonance(13CNMR),gel permeation chromatography(GPC),and differential scanning calorimetry(DSC)were used to study three kinds of polypropylene resins for DC capacitors at home and abroad with different temperature resistance grades,and analyze the effect of microstructure on electrical properties.The results show that the isotactic index,intermolecular chain defect distribution,and molecular weight characteristics jointly affect the crystallization characteristics of polypropylene,and thus affect the final high temperature dielectric properties of materials.The isotactic index of 5 units of imported polypropylene resin is greater than 97%,and the intermolecular chain stereodefect distribution is narrow(I=1.075),the weight average molecular weight is higher and the molecular weight distribution index is larger(PDI>5.6),showing excellent high temperature insulation properties(the electric strengthα=533 kV/mm).While the molecular weight distribution of domestic polypropylene resin is narrow(PDI<5),the weight average molecular weight is lower,the isotactic index of 5 units is less than 97%,and the intermolecular chain stereodefect distribution is wider(I=1.106),which leads to its poor high temperature insulation performance and low electric strength(α=497 kV/mm).

关 键 词：直流电容器 聚丙烯 等规指数 立构缺陷分布 分子量 

分 类 号：TM215.1[一般工业技术—材料科学与工程]