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分子级结构破坏对具有端点和侧点液晶分子聚合物的放松动力学的影响

Diego Becerra¹, Yang Xu¹, Xiaoguang Wang^1,2

¹William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States.

|December 4, 2023

概括

混合端上和侧上液晶聚合物 (LCP) 会破坏其结构,影响热行为和动力学. 调整组合提供了一个调整LCP属性的方法.

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:

侧链液晶聚合物 (SCLCPs) 具有连接到聚合物骨干的液晶 (LC) 组.
液晶聚合物组件可以以端向或侧向的配置连接,从而影响聚合物特性.
这些配置的随机序列可以导致复杂的热行为.

研究的目的:

为了研究SCLCPs的热行为和结构性质,使用随机序列的end-on和side-onLC部分.
了解在混合SCLCP系统中观察到的非单调热趋势的分子水平起源.
探索LC附件类型组合对相位行为和放松动态的影响.

主要方法:

使用粗粒度分子动力学 (MD) 模拟来建模SCLCP系统.
在SCLCP系统上进行了实验研究,用于单个LC部分类型的SCLCP系统进行比较.
分析包括中相特征,结构破坏评估和放松动态评估.

主要成果:

具有随机端上和侧上LC部分的SCLCP表现出非单调的热行为,一些混合物显示的过渡温度低于纯系统.
末端的SCLCPs形成了一个模糊的B型半相,而侧面的SCLCPs显示了一个准六边形的柱状结构.
随机SCLCP的中间组合显示出显著的结构破坏,影响着合和放松动态,特别是高侧面含量.

结论:

由于混合LC附着类型的分子排序的破坏解释了随机SCLCP中观察到的非单调的热行为.
修改LC附件类型的组成为调整SCLCP的相位行为和机械响应提供了一种策略.
了解这些结构性质关系对于设计先进的液晶聚合物材料至关重要.

关键词:

分子动力学模拟,分子动力学模拟纳米结构材料是一种纳米结构材料.阶段过渡阶段过渡阶段过渡放松模块的放松模块是指侧链液晶聚合物侧链液晶聚合物结构 - 财产关系结构.

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