A novel trifunctional epoxy resin (TMBPBTH-EPOXY) was synthesized in our laboratory, and its curing behavior and performance were studied by curing with 4,4'-diaminodiphenylmethane (DDM) with the mass ratio of 30 : 100 of TMBPBTH-EPOXY and DDM. The mixtures of TMBPBTH-EPOXY/DDM were cured at 100, 140, and 160 degrees C, respectively. The curing state was kept for different time from I to 6 h. The transition reaction of epoxide group during curing process was monitored by Fourier transform infrared spectroscopy. It was found that curing reaction was both dependent on the curing temperature and curing time, and the curing temperature has more effect on the curing reaction than the curing time. The curing activation energy was investigated by differential scanning calorimetry to be 55.13 and 55.10 kJ/mol. The glass transition temperature of TMBPBTH-EPOXY/DDM system was 240.2 degrees C. The thermal decomposition temperature at different temperatures and time were studied by thermogravimetric analyzer. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 114: 1976-1983, 2009