干热消毒对聚四氟乙烯驻极体膜电荷储存稳定性的影响

Effect of dry heat antisepsis on charge storage stability for porous polytetrafluoroethylene films

目的:通过对表面电势VS 衰减和开路热刺激放电(open circuit thermally stimulated discharge ,TSD)电流以及准静态压电d33系数测量,研究干热消毒对聚四氟乙烯(PTFE)多孔膜电荷储存稳定性的影响。方法:将PTFE多孔膜分别在室温、150℃和250℃下通过恒压电晕充电制备成驻极体;分别于150℃、250℃中干热消毒150 min;用补偿法、热刺激放电法和准静态法分别测量样品的VS、TSD电流和d33。结果:经150℃和250℃干热消毒150 min, 250℃制备的驻极体保留了初始值的91%和70%,TSD电流谱呈现出与VS 和d33随时间变化类似的实验规律;而以常温制备驻极体的d33分别降至其初始值的48%和15%。结论:高于消毒温度下制备的PTFE多孔膜驻极体具有良好的电荷稳定性,宜采用干热法消毒。

Objective:To investigate the effect of dry heat antisepsis on charge storage stability of porous polytetrafluoroethylene(PTFE) films by measuring the isothermal surface potential(V S) decay,open-circuit thermally stimulated discharge(TSD), and piezoelectric d 33 coefficient. Methods: Porous PTFE films were prepared by constant voltage corona charging at room temperature, 150℃ and 250℃, respectively. PTFE electrets were treated by dry heat antisepsis at 150℃ and 250℃ for 150 min; V S,TSD current and d 33 were measured by the compensation, open-circuit TSD methods and quasi-static, respectively. Results: The piezoelectric d 33 coefficient of porous PTFE electret charged at room temperature decayed to 48% and 21% by dry heat antisepsis at 150℃ and 250℃, respectively. However, the d 33 of electrets charged at 250℃ decayed to 91% and 70%, respectively. Conclusion: The porous PTFE electrets charged at 250℃ has good charge storage stability and is suitable for the method of dry heat antisepsis.