2,3-二二的活交替环开放元解共聚化,以提供完全可降解的聚合物
Taeyang An1, Hanseul Ryu1, Tae-Lim Choi2
1Department of Chemistry, Seoul National University, 08826, Seoul, Republic of Korea.
Angewandte Chemie (International ed. in English)
|October 4, 2023
概括
这项研究介绍了2,3-二二 (DHF) 与周期性烯酸的活交替共聚化,实现了高A,B-交替和受控的分子量. 由此产生的DHF共聚物表现出优异的酸触发降解到单重复单元.
科学领域:
- 聚合物化学 聚合物化学
- 有机合成 有机合成
- 材料科学 材料科学 材料科学
背景情况:
- 2,3-二二 (DHF) 是一种有价值的共同分子,可以通过转化聚合制造刺激响应的可降解聚合物.
- 在具有较低反应性单体的共聚合物中实现高A,B替代,如内三环[4.2.2.02,5]deca-3,9-dienes (TDs) 和内-oxonorbornenes (oxoNBs) 仍然是一个挑战.
研究的目的:
- 为2,3-二二 (DHF) 与TDs和oxoNBs开发一种活生生的交替共聚合方法.
- 增强基于DHF的共聚合物的A,B替代和可降解性.
- 研究 (Ru) 启动器结构对共聚合物特性的影响.
主要方法:
- 使用鲁启动器进行活交替共聚化.
- 控制的变化启动器固体阻碍和单体固体测量.
- 聚合物性质的表征,包括分子量,分散性和A,B交替性.
- 通过H NMR监测的酸触发降解研究.
主要成果:
- 在接近史泰基度的DHF条件下实现的突出的A,B交替 (高达98%).
- 立体阻碍的Ru启动器改善了DHF整合和A,B交替.
- 保持了生活特征:控制的分子量 (高达73.9kDa),狭窄的分散率 (低至1.05),并阻止共聚合物形成.
- 在酸性条件下降解为单重复单元的共聚合物,模型共聚合物的转化率高达80%和检索率高达66%.
结论:
- 建立了一种适用于DHF与循环烯的活交替共聚合的多功能方法.
- 开发的方法可以精确控制共聚合物组成,并增强刺激响应可降解性.
- 这项工作为具有定制性质的先进可降解聚合物提供了一条途径.
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