液晶相转换在聚散板状颗粒悬浮中的液晶相转换
van der Kooij FM1, Kassapidou, Lekkerkerker
1Van't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute, Utrecht University, The Netherlands.
Nature
|September 6, 2000
概括
板状合体形成液晶相,包括一个稳定的柱状二维晶体,即使具有显著的多分散性. 这一发现简化了在合成美索斯科普材料中实现液晶秩序的方法.
科学领域:
- 材料科学 材料科学 材料科学
- 软物质物理学 软物质物理学
- 体科学 体科学 体科学
背景情况:
- 具有自组装结构的体悬浮物在技术上具有重要意义,特别是对于光子材料.
- 非球形的体颗粒,如棒和板,可以形成具有方向和位置顺序的液晶.
- 多分散性 (颗粒大小的变化) 可以阻碍体悬浮中的位置排序.
研究的目的:
- 为了研究板状合体悬浮液的液晶相行为.
- 为了确定颗粒度和多分散性对自组装的影响.
- 为了评估多散系统中有序相的稳定性.
主要方法:
- 板状合物悬浮物的制备和表征.
- 粒子度的系统变化.
- 通过显微镜或散射技术观察相位转换 (同otropic,nematic,columnar).
- 结构秩序和多分散效应的分析.
主要成果:
- 一种板状合体悬浮体呈现出异型,阴性和柱状相,其度越来越高.
- 柱状二维晶相在多分散性方面保持稳定,高达25%.
- 在非常高的颗粒度下,观察到过渡到类似涂料的排序.
结论:
- 合成美索斯科普材料中的液晶秩序可能比先前预期的更容易实现.
- 板状合体为创建具有调节性质的有序结构提供了一个有希望的途径.
- 柱状相对多分散的强度是材料设计的一个重要发现.
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