Kinetics of curing reaction of a diglycidyl ether of bisphenol A/1,3-bisaminomethyl-cyclohexane (DGEBA/1,3-BAC) epoxy resin system

By employing differential scanning calorimetry (DSC) we have studied the kinetic of the cure reaction for a system containing a diglycidyl ether of bisphenol A (DGEBA) and 1,3-bisaminomethylcyclohexane (1,3-BAC) as a curing agent, using an isothermal approach over the temperature range of 60-110°C. We have determined the reached conversions at several cure temperatures and the reaction rates. The results showed that this cure reaction is autocatalytic. The experimental data were compared with the autocatalytic model proposed by Kamal, which includes two rate constants and two reaction orders. This model gives a good description of cure kinetics up to vitrification point. The activation energies for these rate constants were 44-57 kJ mol-1 From the gel time measurements the value obtained for the overall activation energy was 49.5 kJ mol-1.