Synthesis and photopolymerization kinetics of a photoinitiator containing in-chain benzophenone and amine structure

Abstract

A photoinitiator HTD bearing in-chain benzophenone (BP) and coinitiator tertiary amine, based on 4-hydroxybenzophenone (HBP), toluene-2,4-diisocyanate (TDI) and N,N-dimethylethanolamine (DMEA), was synthesized and characterized by ¹H-NMR and UV-vis absorption spectroscopy. HTD had longer absorption wavelength in the UV-vis absorption spectra than the low molecular counterpart BP. The kinetics of photopolymerization was studied by real-time Fourier transformation infrared (FTIR) spectroscopy. It showed that HTD was a more effective photoinitiator than BP. When this photointiator was used to initiate polymerization of acrylates, both rate of polymerization and final conversion increased with increase of initiator concentration and light intensity. UV-vis extract analysis showed that the extractability of HTD was much lower than BP/DMEA on the same environment condition.

Keywords

kinetics / photoinitiator / photopolymerization / benzophenone (BP)/amine