了解碳化合物在水性超分子聚合中的作用:超强非共价结合和合作性
Elisha Krieg1, Haim Weissman, Eyal Shimoni
1Departments of †Organic Chemistry and ‡Chemical Research Support, Weizmann Institute of Science , Rehovot 76100, Israel.
Journal of the American Chemical Society
|June 11, 2014
概括
perfluoroalkyl 链增强水中的超分子聚合强度. 这种化二胺 (1-F) 的非共价结合比其非化对应物 (1-H) 强得多.
科学领域:
- 超分子化学 超分子化学
- 材料科学是一种材料科学.
- 聚合物化学 聚合物化学
背景情况:
- 对于超分子聚合物来说,实现强而可逆的键是具有挑战性的.
- perfluoroalkyl 基具有显著的疏水性,可能增强超分子相互作用.
研究的目的:
- 为了研究一条二胺两上的一种二甲基链是否能在水性环境中增强超分子结合强度.
- 为了比较一种化化合物 (1-F) 与其非化类型 (1-H) 的超分子结构和聚合热力学.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于观察聚合物结构.
- 通过不同的有机共溶剂度来研究超分子聚合和聚合热力学.
- 测量了关联常数以量化非对应性结合强度.
主要成果:
- 化化合物 (1-F) 根据辅溶剂度表现出合作和异构聚合,这与通过冷EM观察到的结构变化有关.
- 1-F 显示出异常强的非共价结合,在75:25水/THF 混合物中,测量的关联常数为1.7 × 10^9 M^-1.
- 在纯水中,1-F的关联常数被推断为至少10^15 M^-1,明显超过了1-H的关联常数.
结论:
- 1-F 的增强聚合强度归因于 perfluorooctyl 组的表面积增加,而不是独特的碳水化合物疏水性.
- 1-F 的聚合机制和合作性的差异与碳链的结构刚性有关.
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