机械变形会影响高度膨胀的聚电解质水凝中的 counterion 凝结
Muzaffar Rafique1, Aykut Erbaş1
1UNAM-Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Turkey. aykut.erbas@unam.bilkent.edu.tr.
Soft matter
|September 26, 2023
概括
聚电解质凝的机械变形会改变离子凝结. 拉伸和压缩凝都增加了离子凝结,特别是在高度膨胀的网络中,揭示了这些材料中复杂的静电反应.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 电化学 电化学 电化学
背景情况:
- 聚电解质凝在机械变形时产生电潜.
- 这种电机械合背后的分子机制尚未完全理解.
- 现有的理论往往侧重于凝中的对电离子凝结或离子条件.
研究的目的:
- 研究在机械应力下在聚电解质凝中产生电潜力的分子起源.
- 量化凝变形过程中对电离子凝结水平的变化.
- 阐明水凝网络结构与静电反应之间的关系.
主要方法:
- 采用了全原子分子动力学模拟.
- 模拟模型聚烯酸水凝在明确的水中.
- 在不同的溶剂含量 (60-90%) 中模拟了单轴压缩和拉伸.
主要成果:
- 在聚合物链周围的对比凝结表现出与拉伸的非单调行为.
- 压缩和拉伸通常都会增加整体的 counterion 凝结.
- 这种效应在微弱膨胀的水凝中不太明显,在多电解质溶液中不存在.
- 水凝拓在变形诱导的离子凝结中起着至关重要的作用.
结论:
- 变形显著影响聚电解质水凝中的 counterion 凝结.
- 这种现象高度依赖于膨胀比率和网络拓.
- 结果突出了变形凝中静电反应的异质性质.
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