变化纳米-蒙特莫里隆含量对环氧介电导率的影响
1Mechanical and Electrical Engineering Institute, Zhongshan Institute, University of Electronic Science and Technology of China, Zhongshan 528400, China.
Molecules (Basel, Switzerland)
|October 16, 2024
概括
纳米-MMT/EP复合材料的接口结构显著影响介电性质. 增加蒙莫里洛诺伊德 (MMT) 含量降低了离子迁移障碍,增强介电导率,直到粒子聚合发生.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 纳米技术纳米技术
背景情况:
- 基于聚合物的纳米复合材料提供可调节的介电性质.
- 接口结构极大地影响了宏观材料的行为.
- 蒙莫里隆 (MMT) 是环氧树脂 (EP) 复合材料中的一个关键纳米填充剂.
研究的目的:
- 为了将纳米-MMT/EP复合材料的接口结构与其介电性质相关联.
- 分析MMT含量对介电极化,损耗和导电性的影响.
- 了解接口形态对离子迁移障碍的影响.
主要方法:
- 使用复合材料技术合成纳米-MMT/EP复合材料.
- 通过XRD,FTIR,SEM和TEM进行微结构性表征.
- 试验测量介电谱和分析介电松.
主要成果:
- 不同的MMT含量会改变纳米复合材料接口形态.
- 介电极化和损耗受到接口变化的影响.
- 较低的离子迁移障碍和观察到的离子导电率增加,MMT含量增加到一个值.
- 超过值MMT含量的颗粒聚合会增加离子迁移障碍.
结论:
- 聚合物分子在接口上的排列规律与MMT含量有关.
- 介电导电率的变化是可预测的,基于受界面结构影响的离子迁移屏障变化.
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