辅助性液晶弹性体中的结构-性质关系 - 间隔器长度的影响
Stuart R Berrow1, Thomas Raistrick1, Richard J Mandle1,2
1School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK.
Polymers
|July 27, 2024
概括
通过使用不同的间隔链长度来研究表现出辅助性行为的液晶弹性体 (LCE). 较短的间距 (4-6个碳) 诱导了辅热性,在考虑玻璃过渡温度时,值汇聚在56%左右.
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
- 材料机械学 材料机械学
背景情况:
- 辅助性材料表现出负波桑比率,在拉伸时横向膨胀.
- 自2018年以来,液晶弹性体 (LCE) 已经表现出辅助性行为,但结构-性质关系仍未得到充分探索.
- 了解分子结构如何影响LCE中的辅助性,对于设计先进材料至关重要.
研究的目的:
- 研究辅助性LCE中的结构属性关系.
- 为了确定间隔链长度对辅助性行为的影响.
- 探索材料动态对辅助性反应值的影响.
主要方法:
- 合成具有不同间隔链长度 (4-7个碳) 的LCE.
- 机械测试以测量波桑比率并确定辅助性值应变.
- 差分扫描热量计 (DSC) 用于确定玻璃过渡温度.
主要成果:
- 在LCE中观察到辅助性行为,其间隔链长度为4至6个碳.
- 辅助性反应的值变异从56% (六碳间隔器) 到81% (四碳间隔器).
- 实现了低至-1.3的Poisson比率; 带有7+碳间隔器的LCEs由于形相形成和故障时的低应变而没有表现出辅助性.
- 对玻璃过渡温度的计算显示,在不同间距长度的间隔器上,约有56%的收性辅助值.
结论:
- 间隔器链长度是实现LCE中辅助性的一个关键因素.
- 材料动力学,特别是玻璃过渡温度,显著影响了辅助性反应.
- 这项研究为设计具有可调节辅助性质的LCE提供了基本的见解.
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