与二甲基甲基甲酸盐混合的5CB的相位平衡和动态:在同位素相位的方向和组成波动的合
Ryoko Shimada1, Osamu Urakawa2, Tadashi Inoue2
1Department of Mathematics, Physics and Computer Science, Japan Women's University, Bunkyo-ku, Tokyo 112-8681, Japan. shimadar@fc.jwu.ac.jp.
Soft matter
|July 1, 2025
概括
将二甲基甲基甲 (DMT) 添加到4--4'-乙 (5CB) 液晶中,会改变相位过渡和动态特性. 构成波动与方向波动相结合,解释了粘度和介电松时间的偏差.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 软物质物理学 软物质物理学
背景情况:
- 4-Cyano-4'-pentylbiphenyl (5CB) 呈现出一种关键的同位素到阴性相过渡.
- 5CB的相位行为和分子动力学对其他化合物的添加敏感.
研究的目的:
- 研究5CB/DMT混合物的相位行为和动态特性.
- 了解二甲基甲甲酸盐 (DMT) 如何影响5CB的液晶特性.
- 为了将相位转换与动力粘度和介电松时间的变化相关联.
主要方法:
- 对5CB/DMT混合物进行实验检查,含有不同度的DMT.
- 基于观察到的过渡温度 (T_IN,T_NC,T_IC) 的相位图构造.
- 使用自由能量模型分析动力粘度 (ν) 和介电松时间 (τ_ε).
主要成果:
- 混合物显示出不同的相变,取决于DMT度 (w_DMT).
- 一个相位图显示了合并过渡温度在3.2%的DMT.
- 动力粘度和介电松时间显示出与预测行为的正偏差,归因于组合方向波动合.
结论:
- 一个结合弗洛里-哈金斯和兰道-德金斯术语的自由能量模型准确地描述了相位图.
- 在同位素相中的组成和方向波动之间的合对于5CB/DMT混合物的动态性质至关重要.
- 这种合解释了观察到的粘度和介电松时间的偏差,并建立了它们之间的关系.
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