We synthesized four diphenylquinoxaline derivatives（SQs） with phenyl-thioether units, which combine photo-cleavable and hydrogen-abstracting groups in one molecule. The photochemistry and photopolymerization of SQs ...We synthesized four diphenylquinoxaline derivatives（SQs） with phenyl-thioether units, which combine photo-cleavable and hydrogen-abstracting groups in one molecule. The photochemistry and photopolymerization of SQs were investigated. SQs possess suitable UV-vis absorption in the range of 350-400 nm with high extinction coefficients. UV-vis and HPLC-MS spectra revealed that C–S bond in phenyl-thioether group of SQs can be broken by irradiation of UV-light. Photolysis and photopolymerization experiments showed that SQs can be used as photo-cleavable photointiators,their photoinitiating efficiency can be enhanced by hydrogen donor. As photo-cleavable photoinitiators,SQs could initiate hexamethylene diacrylate（HDDA） very efficiently with the double bond conversion（DBC） of 80%. In the presence of ethyl-4-（dimethylamino） benzoate（EDB） as coinitiator, photoinitiator systems initiated photopolymerization of commercial acrylate monomers with higher double bond conversion than 90%. These characteristics make SQs potential photoinitiators in photo-curing field.展开更多
基金the National Basic Research Program (No. 2013CB834506)National Nature Science Foundation of China (Nos. 51373098 and 21522403)
文摘We synthesized four diphenylquinoxaline derivatives（SQs） with phenyl-thioether units, which combine photo-cleavable and hydrogen-abstracting groups in one molecule. The photochemistry and photopolymerization of SQs were investigated. SQs possess suitable UV-vis absorption in the range of 350-400 nm with high extinction coefficients. UV-vis and HPLC-MS spectra revealed that C–S bond in phenyl-thioether group of SQs can be broken by irradiation of UV-light. Photolysis and photopolymerization experiments showed that SQs can be used as photo-cleavable photointiators,their photoinitiating efficiency can be enhanced by hydrogen donor. As photo-cleavable photoinitiators,SQs could initiate hexamethylene diacrylate（HDDA） very efficiently with the double bond conversion（DBC） of 80%. In the presence of ethyl-4-（dimethylamino） benzoate（EDB） as coinitiator, photoinitiator systems initiated photopolymerization of commercial acrylate monomers with higher double bond conversion than 90%. These characteristics make SQs potential photoinitiators in photo-curing field.
