Study on Elementary Reaction for Plasma Polymerization Using in situ Mass Spectroscopy

在等离子体聚合物中引入官能团是为等离子体聚合物添加高贵功能所必需的。本文根据等离子体中各种活性中间体的原位质谱学和分子轨道计算结果，讨论了聚合物的离子交换能力与等离子体聚合物的函数关系。同时将用于形成聚合物主链和添加官能团的单体引入反应室。以氟苯和苯氯为单体进行官能团的加成反应。这两种化合物的化学结构非常相似。然而，理论分子轨道计算提供了这些起始单体在血浆中的稳定活性物种的差异。在氟化物的情况下，可以在等离子体聚合物中引入磺酸基团。在氯化物中，磺酸基团可能会被电子攻击而形成其他化合物，包括S元素(磺酸基团的引入是可取的，因为它很容易在碱性溶液中水解成磺酸基)。使用这些起始单体对活性物种进行了原位质谱分析，结果与分子轨道计算结果吻合较好。以氟化物为原料在优化条件下制备的等离子体聚合物薄膜具有较高的离子交换能力，阳离子转移数为0.99，离子电导率为10^~(-4)~(-4)~(-1)；S cm~(-1)~(-1)~(-1)。等离子体聚合物薄膜非常薄，其实际电阻率与商品化的阳离子交换膜(Nafion117)相当。

The introduction of functional group into plasma polymer is necessary for the addition of a noble function to plasma polymer. In this study, an ion exchange ability of polymer was discussed as the function of plasma polymer from the results of in situ Mass spectroscopy and molecular orbital calculation for various active intermediates in plasma. Both monomers for the formation of polymer backbone and the addition of functional group were introduced into a reaction chamber simultaneously. Benzenefluoride and benzenechloride were used as a monomer for the addition of functional group. The chemical structures of both compounds were very similar each other. However, the theoretical molecular orbital calculation provides the difference in the stable active species of these starting monomers in plasma. In the case of fluoride, sulfone group may be introduced in the plasma polymer. In the case of chloride, sulfone group may be attacked by electron to form other compounds including S element (Sulfone is desirable to the introduction of sulfonic acid group, because it can be easily changed to sulfonic acid group by hydrolysis with alkaline solution.) The in situ mass spectroscopy for the active species when using these starting monomers are used, shows the well corresponding result to the expectation from the molecular orbital calculation. The ion exchange ability of the plasma polymer thin film prepared from fluoride under optimized conditions has a high cationic transference number of 0.99 and a high ionic conductivity of 10^<-4>S cm^<-1>. The plasma polymer thin film was so thin that the practical resistivity was comparable with the commercialized cation exchange membrane (Nafion 117) .