Synthesis and characterization of N-isopropyl, N-methacryloxyethyl methacrylamide as a possible dental resin

In this study, N-isopropyl, N-methacryloxyethyl methacrylamide (NIMM) is pr oposed as a possible reactive diluent in place of triethylene glycol dimeth acrylate (TEGDMA) for dental resin mixtures. Real-time infrared spectroscop y was used to monitor the double-bond conversion as a function of irradiati on time, and mixtures of 50/50 wt% bis-GMA/NIMM were found to reach final c onversions (95%) that were 1.5 times greater than bis-GMA/TEGDMA (65%) unde r visible light irradiation. In addition, samples cured to these conversion s were tested with dynamic mechanical analysis. The bis-GMA/NIMM mixture (1 00% converted) was found to have a higher glass transition temperature and modulus at body temperature than a comparable bis-GMA/TEGDMA mixture (60% c onverted). Finally, the water sorption and solubility of bis-GMA/NIMM were determined to be higher than the bis-GMA/TEGDMA comparison, but the values were still within the range of the ISO 9000s standard. These results sugges t that bis-GMA/NIMM mixtures are a viable alternative to conventional denta l resins since a greater degree of monomer conversion is obtainable without sacrificing physical and mechanical properties. (C) 2001 Elsevier Science Ltd. All rights reserved.