聚丙烯的准静态热刺激电流与降温极化效应(英文)

Quasi-static state thermally stimulated current techniques and effect of quenching polarization for polypropylene

用阶跃升温热刺激电流 (TSC)、束缚电荷和剩余电荷等一系列准静态的方法分析了聚丙烯的电荷储存与释放的温度关系 .提出了降温极化和循环变温极化的TSC方法以研究冷冻过程中极化电荷的变化 .三种准静态的TSC谱与2℃ /min升温的TSC谱相比有 -1 5℃的温度移动 .急速降温极化的电流显示出一个充电峰 ,其原因是聚合物在低温时保持了高温态的结构 ,引起了介电常数的突变 ,导致了聚合物存储较多的束缚电荷 .循环变温极化的TSC方法证实了在降温极化过程中束缚电荷进入了较深的能级 .上述循环变温极化的方法有利于制备聚合物驻极体 ,而急速降温不利于高直流电场或辐射条件下使用的聚合物 .

A series of quasi-static state TSC measurement me th ods, step heating TSC, bound charge and residual charge measurements, were perfo rmed to analyze the temperature dependence of charge storage and relaxation for polypropylene. For carefully examining the discharge sources, quenching polariza tion method was proposed to study the variation of stored polarized charges on q uenching process, and then thermal-cycle polarization TSC method was used to ana lyze the effect of quenching polarization further. Three quasi-static state TCS spectra demonstrate a good agreement result of -15?℃ temperature shift relativ e to the spectrum of normal TSC at heating rate 2?℃/min. The quenching polariz ation curent shows a charging peak. The reason is that the structure or configur ation of polymer in high temperature is kept in lower temperature and this struc ture can hold more bound charges in low temperature than charges in high tempera ture. Thermal-cycle polarized TSC measurements show that some bound charges ente r into deeper energy levels in quenching polarization process. Thermal-cycle pol arization provides a better manner for preparation polymer elect ret and the effect of quenching process gives a warning for the polymer used in high DC field or radiation condition.