具有环内极群的形状持久的宏循环:合成,液晶性和二维组织
Matthias Fischer1, Günter Lieser, Almut Rapp
1Max Planck Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany.
Journal of the American Chemical Society
|January 8, 2004
概括
具有极性和基基组的新型宏循环形成稳定的液晶相. 这些分子在柱子内表现出有限的旋转,并且可以纳米功能化表面.
科学领域:
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
- 有机化学 有机化学
背景情况:
- 宏环化合物因其独特的结构和自我组装特性而引起人们的兴趣.
- 液晶 (LC) 呈现有序相,在显示器和传感器中具有应用.
- 控制接口上的分子组织对于纳米技术至关重要.
研究的目的:
- 合成具有特定功能群的新型宏循环 (环内极性,环外基).
- 研究这些宏观循环的液晶行为和分子排序.
- 探索在石墨界面上的宏循环的二维组织和表面功能化能力.
主要方法:
- 宏环化合物的化学合成.
- 极化显微镜观察液晶纹理.
- 用X射线粉末衍射分析LC阶段的分子排序.
- 固态核磁共振 (NMR) 谱学用于研究分子动力学.
- 在溶剂高度定向的烧解石墨 (HOPG) 接口的表面特征.
主要成果:
- 观察到具有风扇形纹理的稳定液晶相,表明柱状分子秩序.
- X射线衍射和固态NMR数据表明,在柱状堆内,宏循环的旋转受到限制.
- 宏循环证明了能够在多纳米尺度上纳米功能化高度定向的烧解石墨 (HOPG) 表面的能力.
结论:
- 合成的宏观循环表现出独特的液晶性质,由它们的特定结构驱动.
- 在柱状相内的受限制的分子旋转影响了材料的散装性质.
- 这些宏循环具有表面纳米功能化应用的潜力.
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