通过依赖溶剂的链形态效应控制的水性超分子聚合
Lorenz Borsdorf1, Lorena Herkert1, Nils Bäumer1
1Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut, Corrensstraße 36, 48149 Münster, Germany.
Journal of the American Chemical Society
|April 13, 2023
概括
通过控制分子构成,溶液与溶剂的相互作用会影响超分子聚合途径. 定制疏水性核心尺寸会影响溶解链与溶剂的相互作用,使水性介质中的路径选择成为可能.
科学领域:
- 超分子聚合物化学
- 材料科学
- 物理有机化学
背景情况:
- 在高分子聚合物科学中,溶液-溶剂相互作用对于分子间的关联至关重要,特别是在水性环境中.
- 了解这些相互作用是解读复杂的自组装能量场景和路径选择的关键.
- 目前关于控制自组合途径的溶解物-溶剂效应的知识仍然有限.
研究的目的:
- 研究溶解物-溶剂相互作用在调节链形状和自组合途径中的作用.
- 探索分子设计,特别是疏水性核心大小,如何影响水性超分子聚合中的这些相互作用.
- 阐明依赖溶剂的形状变化背后的机制及其对聚合途径的影响.
主要方法:
- 基于基乙烯 (OPE) 的波拉性Pt (II) 复合体 (OPE2-4) 的设计和合成,具有不同的疏水性核心大小和相同的三乙烯糖醇 (TEG) 链.
- 在含有不同同溶剂 (THF) 分数的水性介质中进行详细的自组装研究.
- 通过实验研究分析链形状 (延伸,背折叠) 和聚合途径.
主要成果:
- TEG 链包裹疏水核的趋势取决于核大小和同溶剂体积分数.
- 由于TEG链的有效屏蔽,较小的疏水芯 (OPE2) 导致单一可预测的聚合途径.
- 较大的疏水核 (OPE3,OPE4) 呈现出多种形状 (延伸,部分向后折叠,向后折叠),使多种可控的聚合途径具有不同的形态.
结论:
- 溶剂依赖的链形效应是水性超分子聚合的关键和以前被低估的因素.
- 分子设计,特别是疏水性和疏水性组件之间的平衡,允许调节能量格局和选择自组路径.
- 这项工作提供了通过溶液与溶剂相互作用控制复杂的自组合过程的基本见解.
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