多孔聚四氟乙烯/氟代乙烯丙烯共聚物复合驻极体材料的压电效应研究

Study on piezoelectricity of hybrid films consisting of porous PTFE and Teflon FEP

采用高温熔融和电晕充电方法制备了由聚四氟乙烯 氟代乙烯丙烯共聚物复合而成的空间电荷驻极体压电膜 .借助准静态压电系数测量 ,研究了制备工艺对复合膜压电活性的影响 .根据Kacprzyk等提出的复合驻极体膜的压电模型 ,结合等温表面电位衰减和压电系数衰减测量结果 ,讨论了驻极体复合膜系统中的压电性产生机制 .结果表明 ,压电效应的大小不仅取决于俘获在材料中的电荷密度的大小 ,还与被俘获电荷在材料中的存在形式和分布有关 .

The electret hybrid film consisting of porous PTFE and Teflon FEP is prepared through co_melting method at high temperature and with corona charging.Their piezoelectric responses are investigated by means of decay measurement of isothermal piezoelectric coefficient and charge density.The piezoelectric mechanism is discussed according to the theoretical model proposed by Kacprzyk et al. The results indicate that the piezoelectric responses not only result from charge density but also correlate to the charge distribution in the bulk of hybrid film.