Polymethylene Intermediates in Thermal and Photoinduced "Charge-Transfer" Polymerization

热和光诱导“电荷转移”聚合中的聚亚甲基中间体

• 批准号: 8906921
• 负责人: Henry Hall
• 金额: $ 25.73万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-01-01 至 1993-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8906921&HistoricalAwards=false
• 关键词: Polymethylene; Intermediates; Thermal; Photoinduced; Charge

The bond - forming initiation theory proposes that the tetramethylene intermediates, encountered in the cycloaddition reaction of electron-rich with electron-poor olefins, are also the true initiators for the spontaneous polymerizations observed in these systems. Zwitterionic intermediates initiate ionic homopolymerization of either donor and/or acceptor olefin, while diradical intermediates initiate the radical copolymerization. In previous phases of this project, this hypothesis has been proven for a zwitterionic and for a diradical systems. This theory is now being extended to reactions of electron- rich dienes with electron-poor olefins. It is proposed that the spontaneous polymerizations which occur in many of these systems are initiated by a hexamethylene intermediate, which can be either zwitterionic or diradical. In analogy with the thermal reactions, the theory will also be extended to photoinduced polymerization in electron-rich and electron-poor olefin systems. Here again, it is proposed that a tetramethylene intermediate, zwitterionic or diradical, is the initiator of the observed polymerizations.

成键引发理论认为， 环加成反应中遇到的四亚甲基中间体 富电子与贫电子烯烃的反应，也是 观察到自发聚合的真正引发剂 在这些系统中。 两性离子中间体引发离子 给体和/或受体烯烃均聚，而 双自由基中间体引发自由基共聚。 在这个项目的前几个阶段，这个假设已经被 证明了两性离子和双自由基系统。 这个理论现在被扩展到电子反应- 富二烯与贫电子烯烃。 拟议将 在许多这些体系中发生自发聚合 是由一个中间体引发的， 两性离子或双自由基。在类比热 反应，该理论也将扩展到光诱导 在富电子和贫电子烯烃体系中的聚合。 这里再次提出，四亚甲基中间体， 两性离子或双自由基，是所观察到的 聚合。