用陷阱参数作为聚合物电老化特性参数的试验研究

EXPERIMENTAL INVESTIGATION OF THE TRAP PARAMETER AS A CHARACTERISTIC OF ELECTRICAL AGEING OF POLYMER

本文以高分子聚丙烯薄膜材料为试样,在真空与均匀电场中进行加速电老化试验。试验结果表明,试样的老化场强与老化时间呈指数关系。在电老化过程中,用红外光谱分析了试样的内在化学结构变化,用电子顺磁共振测量了老化生成的自由基,用光电导谱和表面电位的测量技术测量了陷阱深度与陷阱密度的变化。试样在电老化过程中,短分子链随时间而增加,陷阱的深度与密度也随时间而增长,都与电老化寿命的经验公式有类似的形式。通过讨论电老化的化学过程,提出陷阱参数可以作为表征材料电老化特性的新参数。本文的结论将为建立新的电老化理论提供了试验依据,并为非损伤性电老化试验创造了前景。

Accelerating tests of electrical ageing for the polypropylene film in vacuum and under uniform stress are taken in this paper. Infrared Spectrum (IR), EPR Spectrum, Photoconductive Spectrum and the Surface Potential Measurement are used to analyze the chemical structure and the deep trap density of the samples respectively. Through the discussion of the chemical reaction of ageing, the pa- per suggests that trap density may act as the new parameter which stands for the characteristic of the electrical ageing of the material.