控制柱状液晶自组装的结构因素
E Johan Foster1, R Bradley Jones, Christine Lavigueur
1Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, Canada V5A 1S6.
Journal of the American Chemical Society
|June 29, 2006
概括
研究人员探索了分子结构如何影响液晶自组装. 较大的芳香核和电子吸收组促进柱状相形成,这对材料特性至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
背景情况:
- 柱状液晶相对于先进的材料是必不可少的.
- 了解分子自我组装是设计功能性材料的关键.
研究的目的:
- 为了研究结构-属性关系,控制盘状分子的自我组装成柱状液晶相.
- 确定分子核心大小和电子性质的变化如何影响液晶相形成.
主要方法:
- 通过凝结反应合成盘状分子.
- 液晶性质和相位行为的表征.
- 使用哈梅特西格玛值对替代效应的分析.
主要成果:
- 较大的芳香核增强了柱状相形成的倾向.
- 提取电子的组促进柱状相,而电子捐赠的组抑制半形态.
- 清除温度显示,随着替代剂的取电子能力的线性增加,清除温度呈现出线性增加.
结论:
- 分子结构,特别是芳香核大小和电子替代物,显著决定了自组装成柱状液晶相.
- 皮-皮相互作用,静电相互作用和分散力对于自组装过程至关重要.
- 圆盘形分子的合理设计可以控制液晶相的行为和特性.
相关概念视频
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