奥利戈 ((p-phenylenevinylene) -联体:在溶液中和固体-液体界面上进行合成和自我组装
Rachid Matmour1, Inge De Cat, Subi J George
1Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
Journal of the American Chemical Society
|October 14, 2008
概括
研究人员合成了新型的类类. 序列决定了自组装成β薄膜双层或螺旋式纳米纤维,影响分子组织.
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
- 生物物理学的生物物理.
背景情况:
- 奥利戈 (p-phenylenevinylene) (OPV) 两性动物在自组装方面进行了探索.
- 序列影响混合材料的自我组装.
- 贝塔片和贝塔转结构具有不同的形状性质.
研究的目的:
- 合成和表征两个新的杂双胞胎.
- 为了研究这些混合两动物在不同环境中的自我组装行为.
- 要了解的二次结构 (β-sheet与β-turn) 如何影响超分子组织.
主要方法:
- 使用了固态和液态合成策略.
- 扫描道显微镜 (STM) 用于2D自组装的亚分子级成像.
- 用光谱技术 (吸收,光,圆形二重化) 和显微镜 (冷-TEM,AFM) 来研究溶液和水中的聚合和自我组装.
主要成果:
- 成功合成了两种混合的双胞胎,OPV-GAGAG (beta-sheet) 和OPV-GANPNAAG (beta-turn),这些两种混合的双胞胎.
- 通过STM观察到,OPV-GAGAG形成了反平行β-sheet双层,通过STM.
- 这两种两性动物都聚合在有机溶剂中;在水中,它们形成了具有螺旋OPV段的自组装纳米纤维,其组织是由序列决定的.
结论:
- 序严格控制了OPV-混合物的自我组装路径和由此产生的纳米结构.
- β-叶片可以促进双层的形成,而β-转会导致水性介质中的螺旋式纳米纤维.
- 这些发现突出了设计具有可调整形态的样功能材料的潜力.
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