聚乙烯膜的介电和粘弹性行为
Jesús G Puente-Córdova1, Flor Y Rentería-Baltiérrez2, Beatriz López-Walle1
1Facultad de Ingeniería Mecánica y Eléctrica, Universidad Autónoma de Nuevo León, Av. Universidad s/n, Cd. Universitaria, San Nicolás de los Garza 66455, Mexico.
Polymers
|December 23, 2023
概括
这项研究研究了聚乙烯 (PVB) 的介电和热性能. 结果显示,界面极化在玻璃过渡温度以上的导电行为中占主导地位,由微积分计算解释.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物物理 聚合物物理
- 介电光谱学 介电光谱学
背景情况:
- 聚乙 (PVB) 是一种多功能聚合物,其应用需要特定的介电和热特性.
- 了解放松过程对于预测不同条件下的PVB性能至关重要.
- 之前的研究已经探讨了PVB的机械性能,但需要进行全面的介电分析,特别是在其玻璃过渡以上.
研究的目的:
- 综合调查聚乙烯 (PVB) 的介电和热性能.
- 分析电放松过程,特别是玻璃过渡和界面极化.
- 通过使用先进的分析技术,阐明PVB在高温下的导电行为.
主要方法:
- 动态电学分析 (DEA) 用于100 Hz至1 MHz的频率范围和293 K至473 K的温度.
- 动态机械分析 (DMA) 用于评估粘弹性行为和玻璃过渡的机械方面.
- 微积分计算,利用一个微积分的德拜模型,被应用来分析介电测量结果.
主要成果:
- 确定了两个主要的电放松过程:玻璃过渡和界面极化.
- 在玻璃过渡温度 (~343 K) 以上,发现界面极化主导了PVB的导电行为.
- 复杂的电模框架为界面极化提供了有价值的见解,与理论预测有很好的相关性.
- 接近1的分数顺序导数值表明玻璃过渡温度以上的显著导电行为.
结论:
- 在温度超过其玻璃过渡时,接口极化在PVB的电导率中起着主导作用.
- 分数计算和复杂的电模是分析像PVB这样的聚合物中介电现象的有效工具.
- 该研究提供了对PVB介电反应的更深入的了解,这对于优化其在各种技术应用中的使用至关重要.
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