灯与激光:一种可见光光启动器,可在低强度下促进激素聚合,在高强度下促进阴离子聚合
Andrea N Zeppuhar1, Daniel E Falvey1
1Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States.
The Journal of organic chemistry
|July 7, 2023
概括
这项研究引入了一种新型的光启动剂,即1-tosiloxy-2-methoxy-9,10-anthraquinone (QT),它可以调节阴离子和激素聚合. 通过调节光强度,QT可实现聚合物和共聚合物的受控合成.
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:
- 可见光响应的光启动器对于受控聚合是至关重要的.
- 人类衍生物提供可调节的光化学性质.
- 对于先进的聚合物合成,双模式启动 (离子和基) 是非常理想的.
研究的目的:
- 在不同可见光强度下研究1-tosiloxy-2-methoxy-9,10-anthraquinone (QT) 的双模式聚合能力.
- 通过使用单一的光启动器,通过阴离子和激素路径证明聚合物的受控合成.
- 通过在聚合机制之间切换,使用单程序合成共聚合物.
主要方法:
- 在不同的可见光照射强度 (高与低) 下,利用1-tosiloxy-2-methoxy-9,10-anthraquinone (QT) 作为光启动剂.
- 在高强度光线下研究对多二硫酸的生成 (阴离子启动).
- 在低强度光下观察DMSO的光氧化,以产生甲基激素 (激素启动).
- 进行乳的环开放聚合和烯酸盐的RAFT聚合.
- 合成一个共聚合物通过一个一个的序列或可切换的聚合过程.
主要成果:
- 在高强度可见光下,QT成功调解了乳的阴离子聚合,通过两光子激发机制产生酸.
- 在低强度可见光下,QT通过光氧化DMSO并产生甲基激素,启动了烯酸盐的基性聚合.
- 该研究表明,通过控制光强度,可以在阴离子和激素聚合机制之间切换.
- 一种共聚合物通过一子程序成功合成,展示了QT双重能力的实际应用.
结论:
- 1-托西-2-甲基-9,10-氨基 (QT) 作为一个多功能的光启动剂,使和基聚合成为可能.
- 光强度是控制QT介导的聚合机制的一个关键参数.
- 开发的单程序为合成复杂的聚合物架构,包括共聚合物提供了一种简化方法.
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