材料期刊网

采用在直流稳态、高频脉冲和交变电场作用下的电晕放电对氟化乙丙烯共聚物(FEP)薄膜材料进行注极,通过等温表面电位测量和热刺激放电技术考察了FEP驻极体的电荷存储特性,依据电晕放电等离子体鞘层模型对实验结果进行了分析,研究了电晕产生模式对FEP薄膜驻极体电荷存储性能的影响.结果表明,电晕注极FEP薄膜驻极体的表面电位稳定性与电晕产生模式、电晕极性有关,但是电荷存储机制只与电晕极性有关.脉冲电晕注极时的稳定性优于稳态电晕注极,但其初始表面电位值较低.交变电场电晕注极获得的驻极体,呈现负极性.不同电晕放电模式在材料表面形成的等离子体鞘层的组成和厚度不同,是FEP驻极体性质不同的主要原因.

The effect of corona discharging mode on the charge storage characteristics of fluorethylenepropylene (FEP) electret film are investigated in this paper.The FEP film was charged by a point-tosurface corona set-up with DC stable voltage,high-frequency impulse power and AC power supply.The charge storage characteristics of FEP electret films were investigated by means of measuring surface potentials and thermal stimulating discharge current.The experimental results are explained by the plasma sheath models based on gas discharge.It is concluded that the charge stability of FEP electrets are correlated to the corona discharging mode and to the corona polarity,however,the charge storage characteristics is only affected by corona polarity.The charge stability of negative polarity electrets is superior to that of the positive polarity electrets.The charge stability when charged with pulse corona is better than that with constant voltage corona,but the initial surface potentials are lesser.The poladty of electrets charged with AC corona is negative.According to the plasma sheath models,the composition and thickness of the plasma sheath will be different when FEP film is charged with different corona discharging mode,which is responsible for the different charge storage characteristics of electrets.