Synthesis and evaluation of 4-benzophenone methoxyl methacrylate as a polymerizable photoinitiator

Abstract

Synthesized 4-benzophenone methoxyl methacrylate (BMM) was used as a polymerizable photoinitiator in combination with 2-(N,N-dimethylamino) ethylmethacrylate (DMEM) to initiate the UV photopolymerization of the mixture of 70 wt % 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy)phenyl]-propane (Bis-GMA) and 30wt% triethylene glycol dimethylacrylate (TEGDMA). Real time infrared spectroscopy (RTIR) was used to monitor the extent of polymerization and dynamic mechanical analyzer (DMA) was used to measure the mechanical properties of the cured samples. Water sorption and solubility of cured samples were tested according to ISO4049's standards. The obtained results indicated that increasing the concentration of DMEM or BMM led to the increase of double bond conversion and the rate of polymerization. Comparing with the non-polymerizable photoinitiating system in the same curing condition, benzophenone(BP)/ethyl 4-dimethylaminobenzoate (EDMAB), BMM/DMEM showed the slightly higher initiating reactivity. The glass transition temperature (Tg), storage modulus, water sorption and solubility of the cured samples initiated by BMM/DMEM were slightly lower than that of samples initiated by BP/EDMAB. © 2008 The Society of Polymer Science.