在拉伸的胆固醇液晶弹性体中显著的异型变形和光学转移
Saki Mori1, Hideaki Takagi2, Nobutaka Shimizu2
1Department of Macromolecular Science and Engineering, Kyoto Institute of Technology, Kyoto, 606-8585, Japan.
Soft matter
|April 26, 2024
概括
胆固醇液晶弹性体 (CLCEs) 在拉伸时显示出明显的光学和机械变化. 它们的螺旋结构发生显著的变化,影响光反射和材料的行为.
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
- 光学是什么?光学是什么?光学是什么?
背景情况:
- 胆固醇液晶弹性体 (CLCE) 是一种先进的材料,其独特的光学特性源于其螺旋分子结构.
- 了解它们的光机械反应对于开发新型智能材料和执行器至关重要.
研究的目的:
- 为了研究在单轴拉伸下CLCEs的光机械行为.
- 识别关键应变值及其对光学和机械性能的影响.
- 分析董事重定向和CLCE内部的结构变化.
主要方法:
- 将CLCEs置于沿x轴的单轴拉伸中.
- 监测传输光谱的变化,中介质的方向,波桑比率和拉伸应力.
- 在xy平面内分析导演重定位.
- 使用毛-特伦捷夫-沃纳模型进行理论解释.
主要成果:
- 在光学和机械特性中观察到依赖应变的交叉.
- 低压力导致蓝色转移和减少反射选择性;高压力停止了音调变化.
- 发生了异型横向收缩 (零波桑比率) 和导演重定位.
- 在临界应变以上,反射选择性丧失,机械性能类似于同位体.
结论:
- CLCEs对单轴应变表现出明显的光机械反应,其特点是行为交叉.
- 毛-特伦特杰夫-沃纳模型有效地解释了这些现象,特别是在调整后的网络异构性.
- 这项研究揭示了在应力下,从性阴性转向非性周期结构的转变.
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