聚苯乙烯基吡啶甲基氧乙烯醚的光化学性质

通过亲核取代反应将苯乙烯基吡啶功能基引入到聚氯甲基氧乙烯醚侧链上,制备出具有聚氧乙烯醚骨架的含有苯乙烯基吡啶盐功能基的线形光功能聚合物,该聚合物具有良好的水溶性.系统研究了上述光功能聚合物以及小分子参比物一氯化-N-丁基苯乙烯基吡啶盐的水溶液在不同紫外光照射下的光化学性质,发现参比物在长波紫外光(波长以365 nm为主)照射下只发生反-顺异构化,而所合成的光功能聚合物在同样紫外光照射下不仅能够发生反-顺异构化,而且能够发生功能基之间的光环加成反应.研究还发现,已经过照射发生光环加成反应的产物,在短波紫外光(波长为254 nm)照射下还可以发生快速光解开环反应.

Photochemical Properties of Poly[oxy[trans-4-(2-phenylethenyl)pyridiniomethyl]-1,2-ethanediyl chloride]

Poly[oxy[trans-4-(2-phenyIethenyl)pyridiniomethyl]-1,2-ethanediyl chioride] (Ⅰ) was synthesized by the nucleophilic substitution of trans-4-(2-phenylethenyl)pyridme with poly(oxy[(iodomethyl)-1,2-etlianediyl]], following by halogen ion exchange with sodium chloride. The photochemical properties of the phenylethenylpyridinium functionalized photosensitive oligomer I as well as the relevant compound N-butyl-4-(2-phenylethenyl)pyridinium chloride (Ⅱ) were thoroughly studied in aqueous solution. It was found that under the irradiation of medium pressure mercury lamp with water cooling glass sheath (λ>310 nm) the only photochemical reaction of Ⅱ is trans-cis isomerization, while, under the same circumstance, I undergoes not (only trans-cis isomerization, but also photocycloaddition. It was also found that under the irradiation of low pressure raercuiy lamp (λ=254 nm) the cycloadded polymer will be photolyzed to form its original linear oligomer.