A new model has been deduced by assumed autocatalytic reactions. It includes two rate constants, k1 and k2, two reaction orders, m and n, and the initial concentration of [OH]. The model proposed has been applied to the curing reaction of a system of bisphenol-S
epoxy resin (BPSER), with4,4'-diaminodiphenylmethane (DDM) as a curing agent. The curing reactions were studied by means of
differential scanning calorimetry (DSC). Analysis of DSC data indicated that an autocatalytic behavior showed in the curing
reaction. The new model was found to fit to the experimental data exactly. Rate constants, k1 and k2 were observed to be greater when curing temperature increased. The activation energies for k1 and k2 were 95.28 and 39.69 kJ mol–1, respectively. Diffusion control was incorporated to describe the cure in the latter stages.