胶束体系中光敏聚合的研究 Ⅴ.离子型二苯酮在不同离子型胶束中光化学行为

STUDY ON PHOTOSENSITIZED POLYMERIZATION IN MICELLAR SOLUTION Ⅴ. THE PHOTOCHEMICAL BEHAVIORS OF IONIC BENZOPHENONES IN THE DIFFERENT IONIC MICELLAR SOLUTIONS

采用水溶性光敏剂——对苯甲酰苄基磺酸钠(BP^-)和对苯甲酰苄基三乙基溴化铵(BP^+)同二苯酮(BP)进行了对比研究。瞬态和稳态光谱的结果表明:BP^+,BP^-分别处于十二烷基磺酸钠(SDS)阴离子胶束和十六烷基三甲基溴化铵(CTAB)阳离子胶束的Stern层,它们在匀相和非匀相体系中的光物理和光化学性质与BP相同。测定了它们在不同离子型胶束体系中的光还原反应速度,结果表明,离子型二苯酮BP^+和BP^-比中性的BP具有更高的反应活性,它们在不同离子型胶束体系中,由于静电相互作用,光还原速度显著不同,在合适的条件下,离子型Bp^+和BP^-在胶束中的光还原速度比中性BP高几十倍以上。另外对胺的疏水性的影响也进行了考察。

Comparative study on the water-soluble photosensitizors, benzoylbenzyl sodium sulfonate (BP-) and benzoylbenzyl trialkylammonium bromide (BP+) with benzophenone (BP) was carried out. The results of the transient and steady spectra indicate that both BP+ and BP- locate in the stern layers of SDS anionic micelle and of CTAB cationic micelle respectively. Their photopysical and photochemical properties in homogeneous and heterogeneous systems are the same as that of BP. The photoreduction rates in the different ionic micellar systems were measured. The results obtained show that the photochemical reactivities of both ionic benzophenones BP+ and BP~ are much higher than that of neutral BP. Their photoreduction rates in the different ionic micellar systems are queit different due to the static electric interaction. Under the appropriate condition, the photoreduction rates of the ionic BP+ and BP- are decades higher than that of neutral BP. The hydrophobic effect of amines was also examined.