苯乙烯基吡啶鎓盐的光二聚反应及其在丝网印刷中的应用

Photodimerization of Styrylpyridinium Salt and Its Application in Silk Screen Printing

甲酰基苯乙烯基吡啶鎓盐(SBQ)是一种具有荧光的水溶性二芳基乙烯衍生物,在水溶液中,在365 nm紫外光照射下发生[2+2]的光二聚反应,得到没有荧光的二聚体。这种光二聚体在254 nm短波长紫外光照射下,可以发生光解开环反应,重新生成单体,恢复荧光。SBQ光二聚体可以作为光信息存储材料。在酸性水溶液中,通过缩醛化反应将SBQ单体接枝到聚乙烯醇骨架上,合成了一种水溶性的感光高分子材料,再与白乳胶复配得到单组分丝网印刷感光胶。同学们利用自己合成的产品不仅可以在纸张和实验服上印刷自己创作的图案,而且还可以动手制作印刷电路板以及开展更多的拓展应用。本实验的合成反应均在水溶液中开展,具有安全、环保和绿色的优点。

Formylstyrylpyridinium salt(SBQ)is a water-soluble fluorescent diarylethene derivative.In aqueous solution,it undergoes a[2+2]photodimerization reaction under 365 nm ultraviolet light irradiation,yielding nonfluorescent photodimers.Upon exposure to 254 nm short-wavelength ultraviolet light,these photodimers can undergo photolysis of the cyclobutene ring,regenerating SBQ monomers and restoring fluorescence,making them suitable for optical information storage.In acidic aqueous solution,SBQ monomers can be grafted onto the polyvinyl alcohol skeleton through acetalization reaction,synthesizing a water-soluble photosensitive polymer material.When mixed with polyvinyl acetate emulsion,it forms a one-component silk screen printing photosensitive emulsion.Students can utilize the synthesized product to print patterns on paper and experimental clothing,as well as to fabricate printed circuit boards and explore additional applications.All synthetic reactions in this experiment are conducted in aqueous solution,offering safety,environmental friendliness,and adherence to green chemistry principles.