吸水对耐温度聚合物的电性能的影响
Kaito Watanabe1, Masahiro Kaneko1, Xianzhu Zhong2
1Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan.
Polymers
|February 24, 2024
概括
水的吸收通过创建导电路径,显著降低了聚胺 (PMDA-ODA,BPDA-PDA) 中的电绝缘. 相比之下,聚乙烯二甲 (PET) 显示的变化很小,这表明聚胺中的水分布局部.
科学领域:
- 材料科学 材料科学 材料科学
- 电气工程 电气工程
- 聚合物科学 聚合物科学
背景情况:
- 聚合物薄膜,如聚胺 (PI) 和聚乙烯二甲 (PET),对于电绝缘至关重要.
- 水的吸收可以显著改变聚合物的电性质,可能导致绝缘故障.
- 了解水引起的降解机制对于材料选择和应用设计至关重要.
研究的目的:
- 研究吸水对特定聚胺 (PMDA-ODA,BPDA-PDA) 和PET电阻和介电常数的影响.
- 阐明这些聚合物在吸水后电绝缘性能恶化的机制.
- 为了确定水和聚胺中电导性的透值.
主要方法:
- 聚合物薄膜 (PMDA-ODA,BPDA-PDA,PET) 被浸入室温纯水中,持续时间不同.
- 量化了水的吸收比率.
- 使用高电阻表测量电阻.
- 用LCR仪在200kHz至2MHz的频率范围内测量了介电常数.
主要成果:
- 在平衡状态下,PMDA-ODA的吸水率为2.7%,BPDA-PDA为2.5%,PET为0.5%.
- 在PMDA-ODA和BPDA-PDA中观察到电导率透值的临界体积分数为0.034.
- 聚乙烯的电阻没有显著下降;它的介电常数是由水和聚合物容量的序列模型解释的.
- 在吸水后,在边缘切割样本上的电阻测量显示了与干燥状态相似的值.
结论:
- 水的吸收导致PMDA-ODA和BPDA-PDA电阻力显著下降,这是由于导电通道的形成造成的.
- 聚胺中吸收的水分子不均分散,而是倾向于在薄膜边缘定位,即使在平衡状态下.
- 与研究中的聚胺相比,PET在吸水下表现出优越的电性能稳定性.
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