结合无金属和金属介导的环开元化聚合,以高效合成瓶刷聚合物
Margaret E Tetzloff1, Andrew J Boydston1,2,3
1Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
ACS macro letters
|June 30, 2025
概括
本研究介绍了一种高效的低金属方法,用于合成使用连续无金属环开放元解聚合 (MF-ROMP) 和金属介导ROMP的瓶刷聚合物. 这种方法简化了宏观农药的制备,并减少了金属催化剂的使用.
科学领域:
- 聚合物化学 聚合物化学
- 宏分子科学 宏分子科学
- 有机合成 有机合成
背景情况:
- 金属介导环开元化聚合 (ROMP) 广泛用于通过接种方法进行瓶刷聚合物合成.
- 使用与主链相同的ROMP机制合成宏观分子具有挑战性,通常需要多步骤程序和高金属催化剂的使用.
- 现有的将可聚合单元连接到ROMP衍生的宏观体的方法通常是多步骤的,金属密集型的.
研究的目的:
- 开发一种更高效,更低金属使用率的方法来合成瓶刷聚合物.
- 为了利用无金属ROMP (MF-ROMP) 进行宏观分子制备和金属介导ROMP进行移植透过聚合.
- 探索在MF-ROMP中使用norbornene imide功能化的乙烯基乙烯启动器.
主要方法:
- 使用无金属ROMP (MF-ROMP) 与norbornene imide功能化乙烯起始剂和四环二烯来创建宏观分子.
- 采用金属介导的ROMP,特别是格鲁布斯的第三代催化剂,用于对宏观素体的norbornene imide链末端进行穿插聚合.
- 进行了宏观分子的内分和外分异构体的比较分析,并从热学上表征了由此产生的瓶刷聚合物.
主要成果:
- 通过MF-ROMP成功合成了宏子,而没有损害norbornene imide单元.
- 通过顺序的MF-ROMP和金属介导的ROMP实现了高分子量瓶刷共聚合物.
- 与传统方法相比,显著减少了金属复合物的使用.
结论:
- 顺序的ROMP-ROMP方法为瓶刷聚合物合成提供了一个高效和低金属使用的策略.
- MF-ROMP提供了一个模块化平台,用于准备功能化宏观分子,适合随后的移植透过聚合.
- 这种方法克服了以前方法的局限性,使复杂的聚合物架构的简化合成成为可能.
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