在环开放聚合物中消除表皮化作用的协同机体催化使得立体正规异聚合物的合成成为可能
Maosheng Li1,2, Yue Tao1,3, Jiadong Tang1,3
1Key Laboratory of Polymer Ecomaterials , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Renmin Street 5625 , Changchun 130022 , People's Republic of China.
Journal of the American Chemical Society
|December 5, 2018
概括
这项研究引入了一种新型的双功能器官催化剂,用于O-碳素化物 (OCAs) 的环开聚合. 这种方法可以在没有单体种族化的情况下实现高同位性聚合物,从而实现功能性聚合物的可持续合成.
科学领域:
- 聚合物化学
- 有机催化剂
- 材料科学
背景情况:
- O-碳素化物 (OCAs) 的环开聚合 (ROP) 可提供功能性聚合物.
- 现有的 ROP 方法通常会导致单体种族化,阻碍立体规律聚合物的合成.
- 开发能够防止表皮化作用的催化剂对于控制的聚合成至关重要.
研究的目的:
- 为OCA聚合开发一种新型的双功能单分子有机催化剂.
- 在没有表皮化的情况下实现OCAs的选择性ROP.
- 合成高同位性聚合物并探索它们的特性.
主要方法:
- 一个双功能单分子有机催化剂的设计和合成.
- O-碳化物 (OCAs) 的环开聚合,特别是曼德利酸OCA (manOCA).
- 由此产生的聚胺酸 (PMA) 的特征,包括分子量和战术性.
- 形成和表征PMA立体复合体
主要成果:
- 这种双功能的催化剂使得manOCA的选择性ROP能够在最小的表皮化过程中实现.
- 合成了具有控制分子量 (高达19.8公斤mol-1) 的高同位性聚胺酸 (PMA).
- 形成了第一个PMA反体的晶体立体复合体,其点在150°C左右.
- 催化剂显示出水分稳定性,可回收性和易于使用.
结论:
- 一种新的双功能器官催化剂为OCAs的立体选择性ROP提供了有效的途径.
- 这种方法可以实现立体常规功能聚合物的可持续和可扩展的合成.
- 形成晶体立体复合物的能力为功能性聚材料开辟了新的途径.
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