利用荧光探针技术研究氧鎓盐光引发丁基乙烯基醚的阳离子聚合

PHOTO-INITIATED CATIONIC POLYMERIZATION OF BUTYL VINYL ETHER (BVE) BY PYRYLIUM SALTS

本工作合成了一组带不同取代基的氧鎓盐化合物,并对它们的荧光寿命、荧光量子产率以及用丁基乙烯基醚(BVE)进行猝灭的荧光猝灭常数进行了测定,发现带拉电子基的氧鎓盐化合物和BVE间存在着较强的相互作用,相反,推电子基的引入则减弱了这种影响,表明反应具有电子转移性质.由于在BVE的聚合过程中,被猝灭的氧鎓盐荧光会因BVE聚合、双键减少而使氧鎓盐荧光逐步恢复.因此利用这一现象作为荧光探针,考察了氧鎓盐光引发BVE的阳离子聚合过程.文中还对氧鎓盐光引发BVE聚合的机理进行了初步讨论.

A group of pyrylium salts with different substituents has been synthesized in this work. Their fluorescence life time, quantum yield and quenching constant by BVE have also been measured. It was found that a strong interaction was observed between BVE and pyrylium salt which contains an electron-withdrawing group, and contrary, the introduction of electron-repulsive groups to the pyrylium salt will decrease this effect. It indicated that these reactions possess the characteristic of electron transfer. Because, the amount of double bond of BVE decreases in the process of BVE polymerization, therefore, in the same time the quenched fluorescence of pyrylium salt can be recovered gradually. This phenomenon may be used as a probe for studying the process of photo-induced initiated cationic polymerization of BVE. A preliminary mechanism for the photo-initiated polymerization of BVE by pyrylium salt was also discussed.