用自主开发的解卷分析程序研究烯,乙烯,烯和乙烯聚合物的介电松,以烯为单体和乙烯聚合物
Youngil Moon1, Gyunghyun Kim2, Jaekap Jung3
1Department of Electrical Engineering, Pohang University of Science and Technology, Pohang 37673, Gyeonsangbuk-do, Republic of Korea.
Polymers
|June 13, 2025
概括
本研究使用介电光谱学分析了酸丁 (NBR),乙烯--二烯单体 (EPDM) 和电 (FKM) 的介电性质. 结果揭示了不同的放松过程,并有助于理解材料科学应用中的聚合物行为.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 介电光谱学 介电光谱学
背景情况:
- 像NBR,EPDM和FKM这样的弹性体在各种工业应用中至关重要.
- 了解它们的介电性质对于材料的表征和性能预测至关重要.
- 以前的介电分析往往缺乏复杂的放松现象的详细解卷.
研究的目的:
- 对NBR,EPDM和FKM聚合物的介电特性进行综合分析.
- 精确地解卷介电谱,并识别各种放松现象和直流导电过程.
- 为了确定这些弹性体的激活能量和玻璃过渡温度.
主要方法:
- 在频率和温度的广泛范围内获取介电分散光谱.
- 使用自己开发的"分散分析"程序,精确解卷介电谱.
- 应用Arrhenius模型来确定激活能量和VFTH定律来估计玻璃过渡温度.
主要成果:
- 确定了α,α",β和γ放松现象,以及NBR中的DC导电.
- 在EPDM和FKM中观察到α,β放松,马克斯韦-瓦格纳-西拉斯 (MWS) 过程和DC导电.
- 通过介电光谱测试确定了二次放松和直流导电的激活能量,并通过介电光谱测试估计了玻璃过渡温度 (Tg),显示了与DSC的良好一致.
结论:
- 这项研究为NBR,EPDM和FKM的介电性质提供了基础的见解.
- 识别的放松机制和确定的参数为未来的聚合物介电材料研究提供了全面的参考.
- 介电光谱学,结合先进的分析,是一个强大的工具来表征弹性体的行为.
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