Copolymeric photoinitiators containing in-chain thioxanthone and coinitiator amine for photopolymerization

Two kinds of copolymeric macromolecular photoinitiator, PTXPM and PTXPC, were prepared by introducing methylacryloyl or cinnamoyl groups to the side chain of PTXP. The photopolymerizations of poly(propylene glycol)diacrylate (PPGDA) and trimethylolpropane triacrylate (TMPTA), using PTXPM and PTXPC as photoinitiators, were studied by photo-DSC. PTXPM and PTXPC have UVvis spectra similar to that of PTXP with blue-shift absorption maxima. The photopolymerization behavior of TMPTA, initiated by three photoinitiators, appears similar to that of PPGDA. Compared with PTXP and PTXPC, PTXPM gives higher polymerization rate and final conversion, in photopo lymerization of PPGDA and TMPTA, which shows that the introduction of methyl acrylate to the PTXP chain has a greater effect on photopolymerization of PPGDA and TMPTA than that of cinnamoyl acrylate. The polymerization rate and final conversion, for photopolymerization of PPDGA initiated by PTXP, can be more effectively increased by the introduction of methyl acrylate group to the PTXP chain, than are those for TMPTA. ©2004 Wiley Periodicals, Inc.