可见光诱导的异构乙烯阴性聚合:一种通向合成终端功能性聚乙烯的途径
Maksim Hulnik1, Diana Trofimuk1,2, Pavel A Nikishau1
1Research Institute for Physical Chemical Problems of the Belarusian State University, 14 Leningradskaya st., 220006 Minsk, Belarus.
ACS macro letters
|July 27, 2023
概括
可见光启动异构乙烯的阴离子聚合,使用二二甲二甲 (Mn2(CO) 10) 和二酸六酸 (Ph2I+PF6-) 系统. 这种方法可以产生具有可控性质的低分子量聚乙烯.
科学领域:
- 聚合物化学 聚合物化学
- 摄影化学的使用.
- 有机合成 有机合成
背景情况:
- 可见光诱导聚合为传统方法提供了更绿色的替代方案.
- 阴离子聚合需要精确控制启动和传播步骤.
- 光启动系统对于在暴露在光线下启动聚合是至关重要的.
研究的目的:
- 开发一种新的可见光诱导的异布乙烯 (isobutylene) 阴性聚合系统.
- 合成低分子量聚乙烯,具有受控的分子量和高的外烯含量.
- 为了研究光启动和聚合物形成的机制.
主要方法:
- 在存在二二甲二甲 (Mn2(CO) 10) /二二六酸 (Ph2I+PF6-) 光启动系统的情况下对异布烯进行可见光照射.
- 通过激素中间体生成甲基异甲基碳酸.
- 通过调整二胺盐的度来控制分子量.
主要成果:
- 成功合成了低分子量聚伊索布丁烯 (Mn = 2000-3000 g mol-1) 的低多分散性 (Đ <1.7).
- 在合成的聚乙烯中获得了高含量的外烯末端组 (高达90%).
- 通过改变光启动器度来证明对聚乙烯分子量 (2000-12000 g mol-1) 的控制.
- 使用相同的光启动系统合成的聚β-烯 (Mn = 5000 g mol-1 , Đ ≈ 2.0) .
结论:
- Mn2(CO)10/Ph2I+PF6-系统有效地启动可见光诱导的异布烯的阴离子聚合.
- 该方法允许合成精确定义的低分子量聚乙烯,具有理想的终端组功能.
- 光启动系统表现出多功能性,使其能够合成其他聚合物,如聚β-烯.
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