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首页> 外文期刊>Journal of Applied Polymer Science >Photoinduced living cationic polymerization of tetrahydrofuran(IV): Syringe method
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Photoinduced living cationic polymerization of tetrahydrofuran(IV): Syringe method

机译：四氢呋喃（IV）的光诱导活性阳离子聚合：注射法

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摘要

The living nature of cationic poly(tetrahydrofuran), which is generated by the addition of the photolytic products of diphenyliodonium hexafluorophosphate (initiator) via syringe, was investigated in connection with the direct polymerization method in which polymerization of tetrahydrofuran is carried out in the presence of the initiator. Although the living nature of the polymerization (i.e., the linear relationship between the percentage of conversion and the molecular weight of the resulting polymer) is observed in the syringe method because of the absence of chain transfer or termination, unexceptionally, a lower rate of polymerization and higher molecular weights of the resulting polymers were observed in the syringe method when compared with those of the corresponding direct polymerization method. This leads us to the conclusion that the living nature is ascribed to the stabilization of the propagating cationic species due to ion pair formation with the less-nucleophilic complex metal halide anion (PF6-), and the decreased rate of polymerization and higher molecular weight in the syringe method is attributed to the partial loss of the activity of the cationic species because of the nucleophilic attack of basic impurities, such as water, introduced to the system in the syringe manipulation. (C) 2002 John Wiley Sons, Inc. [References: 18]
机译：通过直接聚合法研究了阳离子聚四氢呋喃的活性，该阳离子聚四氢呋喃是通过注射器添加二苯基碘化六氟磷酸酯的光解产物（引发剂）而产生的，该直接聚合法是在存在以下条件下进行四氢呋喃的聚合反应的启动器。尽管由于没有链转移或终止，在注射方法中观察到了聚合的活性（即转化率与所得聚合物的分子量之间的线性关系），但是聚合速率较低与相应的直接聚合法相比，在注射器法中观察到了更高的分子量和更高的分子量。这导致我们得出以下结论：由于与亲核性较低的复杂金属卤化物阴离子（PF6-）形成离子对，并且由于聚合反应速率降低且分子量较高，因此，活泼的性质归因于正在传播的阳离子物种的稳定。注射器方法归因于由于在注射器操作中引入系统的碱性杂质（例如水）的亲核攻击，阳离子种类的活性部分损失。 （C）2002 John Wiley Sons，Inc. [参考：18]

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