该文在总结分析不同研究者对各种形态聚丙烯驻极体特性研究成果的基础上,采用短路热刺激放电技术研究了不同形态PP驻极体的电荷存储特性,依据热刺激放电理论对实验结果进行了分析,确认薄膜聚丙烯存在两种类型的空间电荷陷阱,一类为表面阱,另一类为体阱;而熔喷聚丙烯只有体阱空间电荷,且其热刺激放电峰峰温随结晶度的增加而增加,而结晶度与材料来源、驻极体形成工艺密切相关,这是造成不同研究者所获结果不同的主要原因。由热刺激放电理论中的初始上升法获得的结果表明:熔喷和薄膜聚丙烯驻极体的电荷束缚能随峰温的增加而增加,但弛豫时间随束缚能的上升而减少。
The charge storage characteristics of polypropylene (PP) electrets for different morphology were studied by means of short-circuit thermally stimulated discharge technique. It is confirmed that there are two types of space charge traps, shallow and deep, in the PP film, but there was only one kind trap-deep trap in the melt-blown PP web. The peak temperature of short-circuit thermally stimulated curreat with the increase of crystallinity in melt-blown PP web. The trap energy and relaxation time according to the peak temperature by means of the initial rise method of thermally stimulated becomes higher were calculated discharge tech- nique. The results show that the trap energy increases but the relaxation time decreases with the increase of the peak temperature. The charge storage characteristics depend on its crystalline state in PP electrets, which is the main reason causing the different results of thermally stimulated discharge for different researchers.