由二极聚合驱动的双极聚合驱动的双极聚合和基染料的高分子聚合和凝形成
Sheng Yao1, Uwe Beginn, Tobias Gress
1Institut für Organische Chemie, Universität Würzburg, Am Hubland, D-97070 Würzburg, Germany.
Journal of the American Chemical Society
|July 1, 2004
概括
通过聚合,两种梅洛胺染料通过聚合形成超分子聚合物. 这些聚合物表现出溶剂依赖的行为,导致凝结并形成硬的棒状组件,在材料科学中具有潜在的应用.
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
- 聚合物化学 聚合物化学
背景情况:
- 墨氨酸染料是高度双极的分子,具有自我组装的潜力.
- 刚性链接器可以预先组织分子以进行受控的超分子聚合.
- 了解聚合行为是设计新材料的关键.
研究的目的:
- 为了研究附着梅洛氨酸染料的高分子聚合.
- 为了描述不同类型的染料聚合物形成.
- 为了阐明由此产生的超分子组件的结构和质性质.
主要方法:
- 紫外/紫外光谱法用于监测染料聚合和溶剂效应.
- 粘度测量和风湿学研究溶液和凝的特性.
- 原子力显微镜 (AFM) 和冷传输电子显微镜 (cryo-TEM) 用于结构分析.
- 通过X射线衍射来研究固态结构.
主要成果:
- 观察到单体染料和D型和H型聚合物之间的依赖溶剂的平衡.
- 聚合物表现出高的内在粘度,这表明了宏分子行为.
- 由于基链纠,化发生在较高度下.
- AFM,冷-TEM和X射线衍射揭示了长,硬,棒状的超分子组合,具有柱状半形态.
- 一个结构模型提出了六条交织在一起的线条,形成一个直径为5纳米的棒,带有管状染料聚合.
结论:
- 绑定的美洛胺染料可以通过分子间聚合进行超分子聚合.
- D-和H-聚合物的形成依赖于溶剂,导致不同的组装类型.
- 超分子聚合物形成了负责凝的纠网络,并表现出液晶性质.
- 一个详细的结构模型解释了刚性,棒状组件的形成,具有非局部化的激发性状态.
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