乙烯基-尿氨酸玻璃剂:通过结合加速和抑制网络动力学
Stéphanie Engelen1, Neil D Dolinski2, Chuqiao Chen2
1Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, 9000, Ghent, Belgium.
Angewandte Chemie (International ed. in English)
|January 10, 2024
概括
乙烯基同型尿素 (VUN) 和乙烯基同型尿 (VUO) 动态聚合物网络具有可调节的反应性. 混合VUN和VUO可以通过结加速键交换,从而实现新的材料设计.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
背景情况:
- 乙烯基类尿 (VUO) 网络作为无催化剂的玻璃体,具有温度依赖的键交换.
- 与VUO相比,vinylogous尿素 (VUN) 在溶液中表现出较快的键交换.
- 以前,具有相似结构的VUO和VUN玻璃仪显示了可比的网络动态.
研究的目的:
- 为了研究乙烯基标记性尿和乙烯基标记性尿素聚合物网络的动态行为.
- 探索混合VUO和VUN连接对网络动态的影响.
- 了解分子间键在调节聚合物网络反应性的作用.
主要方法:
- 合成基于乙烯基体尿 (VUO) 和乙烯基体尿素 (VUN) 的聚合物网络.
- 使用应力放松和爬行测试来描述网络动态.
- 对混合VUO/VUN网络进行分析,以确定不同组合的影响.
主要成果:
- 具有相似架构的VUO和VUN玻璃膜显示了可比的应力放松和爬行行为.
- 混合VUO和VUN链接显著加速了动态共价键交换.
- 在VUN部分的分子间结被确定为影响债券汇率的关键因素.
结论:
- 在vinylogous尿素链接中的分子间键可以催化聚合物网络中的共价键交换.
- 在高度下,结导致相位分离,并限制了聚合物动态.
- 通过控制可调节性质的VUN/VUO比率来建立动态聚合物材料的简单设计原则.
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