通过乳/烯混合物的正交 (解) 聚合,关闭"一个单质-两个聚合物-一个单质"循环
Changxia Shi1, Ryan W Clarke1, Michael L McGraw1
1Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States.
Journal of the American Chemical Society
|January 27, 2022
概括
本研究引入了一种新型的双环单体,可通过环开聚合或环开转化聚合实现直角聚合,产生不同的聚合物或多环烯. 这两种聚合物在温和条件下可回收成原始单体.
科学领域:
- 聚合物化学
- 材料科学
- 有机合成
背景情况:
- 传统的低天花板温度 (LCT) 单体,如γ-烯酸 (γ-BL) 和环烯,对聚合具有挑战性.
- 现有的方法往往缺乏对聚合途径和脱聚合的正交控制.
研究的目的:
- 开发一种能够进行直角聚合和脱聚合的混合双环单体 (BiL=).
- 从单个单体中制造出两种不同的聚合物类型:聚和聚烯.
- 实现受控的聚合,后功能化和有效的化学回收.
主要方法:
- 一种新的双循环乳/烯混合单体 (BiL=) 的合成.
- 使用环开聚合 (ROP) 和环开元聚合 (ROMP) 催化剂进行正交聚合.
- 由此产生的聚合物 (P(BiL=) ROP和P(BiL=) ROMP及其脱聚物化产品的特征.
- 完整的功能组的后功能化,用于属性调整.
主要成果:
- 混合单体 (BiL=) 成功经历正交ROP和ROMP,分别产生聚和功能化聚烯.
- 这两种聚合物都具有热强度,在温和的条件下 (25-40°C) 可化学回收到单体.
- 在ROP中实现了受控的聚合,包括拓和立体化学控制.
- 完整的功能组允许聚合后的修饰,调整材料的特性.
- 证明了共聚物和复合物的选择性脱聚变为起始单体.
结论:
- 一种多功能双循环单体使直角聚合和脱聚合成为可能,提供了各种聚合物架构的访问.
- 开发的聚合物具有热稳定性和化学可回收性,符合可持续材料原则.
- 这种策略为设计具有可调节性质的高级功能材料提供了一个强大的平台.
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