聚合物的粗粒度建模,其末端和侧面的液晶部分:建筑的影响
Diego Becerra1, Pranav R Jois2, Lisa M Hall1
1William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, USA.
The Journal of chemical physics
|June 8, 2023
概括
具有不同架构的侧链液晶聚合物 (SCLCP) 呈现出不同的相位过渡行为. 端式SCLCP显示的过渡温度高于侧式SCLCP,为设计响应性材料提供了洞察力.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 软物质物理学 软物质物理学
背景情况:
- 液晶 (LCs) 是中产物分子,可以自组织成有序的相位.
- 侧链液晶聚合物 (SCLCPs) 将LC组集成到聚合物架构中,将LC和聚合物的特性结合起来.
- 液晶电路的排序影响了聚合物链的形状,导致通过液晶电路到同位素过渡进行加热后发生宏观形状变化.
研究的目的:
- 研究不同架构的SCLCP中的结构-属性关系.
- 了解侧链的长度,刚度和附着类型如何影响LC相位行为.
- 探索聚合物架构对热过渡和形状变形的潜在影响.
主要方法:
- 为SCLCPs开发一个粗的计算模型.
- 包括扭力潜力和盖伯恩型LC相互作用.
- 模拟具有不同侧链长度,链度和LC连接配置 (端对和侧对) 的系统.
- 分析温度的函数的结构性质和相变的分析.
主要成果:
- 模拟的SCLCP系统在低温下形成了组织良好的中相结构.
- 与相似的侧面系统相比,终端的SCLCP架构表现出较高的液晶-同位素过渡温度.
- 该研究证实了相位过渡对聚合物结构的依赖性.
结论:
- 这些发现为深入了解SCLCP中的阶段过渡提供了更深入的理解.
- 定制SCLCP架构,特别是LC附件类型,可以控制过渡温度.
- 这种知识对于设计具有可控制和可逆变形的先进材料非常有价值.
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