在一维协调聚合物中的机械诱导的多态性
Taichi Nishiguchi1, Yuki Ohara1, Kentaro Kadota2
1Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University Katsura, Nishikyo-ku Kyoto 615-8510 Japan.
Chemical science
|December 6, 2024
概括
机械力在协调聚合物中产生不同的无形状态. 这些状态表现出不同的玻璃过渡温度和结构方向,观察到可逆过渡.
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
- 固态化学 固态化学
背景情况:
- 协调聚合物是具有调节性质的多功能材料.
- 无形材料缺乏远程秩序,导致独特的物理特性.
- 机械力可以影响材料的结构组织和特性.
研究的目的:
- 研究在机械剪切下协调聚合物中不同无形结构的形成.
- 描述这些无形状态的不同性质,包括玻璃过渡温度和结构方向.
- 探索这些无形状态之间的过渡的可逆性.
主要方法:
- 一个一维协调聚合物的合成和表征,Cu (Tf2N) 2 (bip) 2.
- 应用静态和振荡式切削力来诱导不同的无形状态.
- 使用X射线吸收细结构 (XAFS) 和小角度X射线散射 (SAXS) 分析结构差异.
- 使用动态机械分析 (DMA) 调查过渡.
主要成果:
- 协调聚合物的两个不同的无形状态是由静态和振荡剪切形成的.
- 静态无形状态在-10°C时表现出玻璃过渡,而动态无形状态在70°C时表现出过渡.
- XAFS和SAXS揭示了两个无形状态之间的结构导向差异.
- 动态机械分析证实了这两个无形状态之间的可逆过渡.
结论:
- 机械切削力在协调聚合物中有效地产生了不同的无形状态.
- 无形状态在它们的玻璃过渡温度和结构特征上有所不同.
- 这些机械诱导的无形状态之间的可逆过渡是可以实现的,为响应性材料提供了潜力.
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