种子超分子聚合物的动力屏障的分子工程
Qin Huang1, Nicolas Cissé1, Marc C A Stuart2
1Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Journal of the American Chemical Society
|February 24, 2023
概括
这项研究通过设计具有可调键的分子来设计种子超分子聚合 (SSP) 的动力障碍. 这种控制允许一种新的动力模型,其中单体激活,而不是种子度,决定了聚合率.
科学领域:
- 超分子化学
- 聚合物科学
- 化学工程
背景情况:
- 种子超分子聚合 (SSP) 能够控制复杂结构的合成.
- 目前的SSP方法受到控制键相互转换的低动力障碍所限制.
- 精确控制超分子组合需要设计这些动力障碍.
研究的目的:
- 通过复杂的分子设计在种子超分子聚合 (SSP) 中设计动力障碍.
- 研究分子设计对单体稳定性和聚合动学的影响.
- 根据实验观察到的现象开发SSP的新动态模型.
主要方法:
- 设计了具有稳定的分子内环 (三胺) 和外围胺基组的新型构件,促进分子间相互作用.
- 合成了一系列具有不同外围侧链体积的分子, 以系统地增加动力稳定性.
- 研究了种子度对聚合率的影响,并分析了能源格局.
- 进行异种种植实验以研究聚合抑制和触发.
主要成果:
- 在单体形式中成功设计了具有增强动力稳定的分子.
- 观察到播种速率常数与种子度不成比例,这表明除了简单的播种之外的速度限制步骤.
- 提出了一个新的动力模型,其中单体激活是决定速度的步骤.
- 已证明的异质种植可以抑制或触发聚合,这取决于构建块.
结论:
- 分子设计提供了一个强大的策略来控制SSP中的动力障碍.
- 这种工程SSP系统的速度决定的步骤是单体激活,而不是种子度.
- 了解能量格局和异质播种效应可以更深入地了解超分子聚合控制.
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