Investigation of 3,4-methylenedioxybenzene methoxyl methacrylate as coinitiator and comonomer for dental application.

In this study, 3,4-methylenedioxybenzene methoxyl methacrylate (MDBMM) was synthesized for the purpose of replacing both triethylene glycol dimethacrylate (TEGDMA) and tertiary amine, which was usually used as a comonomer and coinitiator for dental resin, respectively. Urethane dimethacrylate (UDMA) was chosen as a monomer. Real time near Fourier transform infrared (FTIR) with a horizontal sample holder and dynamic mechanical analyzer (DMA) were used to study the kinetics and mechanical properties, respectively. The results showed that the addition of MDBMM as a coinitiator in UDMA/TEGDMA/CQ (70/30/0.5 wt %) system led to the increase of the rate of polymerization. When compared with the commercial polymerizable amine, 2-(N,N-dimethyl amino)ethyl methacrylate (DMEM), MDBMM showed comparable initiating reactivity and led to higher modulus around human body temperature (37 degrees C). MDBMM as a comonomer resulted in slightly higher final double bond conversion than that of TEGDMA, which brought higher modulus around 37 degrees C. Therefore, MDBMM can be used as both potential coinitiator and comonomer for dental application.