正充电聚四氟乙烯薄膜驻极体的电荷储存及其动态特性

Charge storage and its dynamics in positively corona charged polytetrafluoroethylene film electrets

研究了栅控恒压正电晕充电的聚四氟乙烯 (PTFE)薄膜驻极体的电荷储存与输运特性 .结果显示在 10 0℃以下的较低温区和高于 15 0℃ ,尤其是高于 180℃的较高温区内慢再俘获效应控制着脱阱电荷的输运 ;而在约 10 0—15 0℃的温区内快再俘获效应占主导地位 .初始表面电位的增加将导致电荷密度衰减加剧 ,通过合理控制充电参数和组合热处理工艺 ,可使同样储存有足够高的电荷密度的正负充电的PTFE薄膜驻极体既显示出相近的电荷储存寿命 。

In this paper, charge storage and its dynamics in positively corona charged polytetrafluoroethylene(PTFE) film electrets have been studied. It is found that from room temperature to 100℃ and from about 150℃, especially from 180℃ to higher temperatures, slow retrapping controls the transport of detrapped charge; however, from about 100℃ to 150℃ the fast retrapping plays a dominant role. The increase of the initial surface potential will lead to a significant decay of charge density, so by means of properly controlling the charging parameter and the heat treatment process we can get positively and negatively charged PTFE film electrets with the same charge density, which not only have a similar charge storage life but also an outstanding charge storage stability.