화학공학소재연구정보센터
Journal of Polymer Science Part A: Polymer Chemistry, Vol.44, No.12, 3738-3750, 2006
Highly efficient, polymerizable, sulfur-containing photoinitiator comprising a structure of planar N-phenylmaleimide and benzophenone for photopolymerization
In a continuation of research on chemically bonded photoinitiators comprising a structure of planar N-phenylmaleimide (NPMI) and benzophenone (BP), a novel, highly efficient, polymerizable, sulfur-containing photoinitiator, 4-[(4-maleimido) thiophenyl]benzophenone (MTPBP), was synthesized by the introduction of an NPMI group into BR Another chemically bonded photoinitiator, 4-[(4-maleimido)phenoxy] benzophenone (MPBP), was selected to evaluate its photoefficiency. The results showed that MTPBP possessed a greatly redshifted UV maximal absorption and a very weak fluorescence emission. Electron spin resonance spectra indicated that the C-S bond in its molecule underwent photolysis reactions to generate radicals to initiate the polymerization. Three representative types of different functionality monomers-methyl methacrylate, 1,6-hexanediol diacrylate, and trimethylolpropane triacrylate-were chosen to be initiated through dilatometry and differential scanning photocalorimetry with unsaturated tertiary amine NN-dimethylaminoethyl methacrylate as the coinitiator. The results showed surprisingly high efficiency of MTPBP due to the mutual influence between NPMI and BP as in their physical mixtures and photolysis reactions at the C-S bond. Both MPBP and MTPBP behaved with similar regularity toward different monomers. (c) 2006 Wiley Periodicals, Inc.