Packet-like Space Charge Dynamics in Polyethylene with Various Crystallinity
Packet-like space charge behavior in polyethylene was firstly indentified in the early 1990’s. Much effort has been done to clarify it in physical essence. The space charge density and migrating velocity of space charge packet are of the two main parameters to characterize this phenomenon. The micro-structure could significantly influence charge trap density and trap level, which therefore influence the space charge migration. In this study, linear low density polyethylene (LLDPE) samples with various crystalline rate and gradient crystalline were prepared by hot pressing process with controlling cooling rate. The evolution of space charge packet in the LLDPE samples sandwiched by semiconducting electrodes under DC 40MV/m stress at 40℃ was monitored by pressure wave propagation (PWP) method. The influence of crystallinity and micro-morphology on charge injecting rate, mobility and decaying procedure in LLDPE are discussed. The results show that the heating process history could significantly influence the dynamics of packet-like space charge.
polyethylene space charge cooling rate crystallinity
Hui Zhao Feihu Zheng Yewen Zhang
Pohl Institute of Solid State Physics, Tongji University 1239 Siping Road, Shanghai 200092, China
国际会议
哈尔滨
英文
879-882
2009-07-19（万方平台首次上网日期，不代表论文的发表时间）