Analysis of a dimethacrylate copolymer (Bis-GMA and TEGDMA) network by DSCand C-13 solution and solid-state NMR spectroscopy

In this work the effect of dilution with TEGDMA on the kinetics of Bis-GMA polymerization and on the extent of polymerization or degree of conversion was studied using (a) DSC and (b) NMR, The systems with lower viscosity and lower T-g exhibited higher extent of polymerization, For Bis-GMA/TEGDMA mi xtures the calculated T-g values were found to be higher than the experimen tal values suggesting that a dilution effect is predominant rather than int ermolecular hydrogen bonding. Solid state NMR has been shown to be a conven ient method for measuring the total amount of conversion in a mixed monomer system. The disappearance of the NMR solution spectrum was used to reveal overall polymerization kinetics. (C) 2000 Elsevier Science Ltd. All rights reserved.