Curing Kinetics of Diglycidyl Ether of Bisphenol A and Diaminodiphenylmethane Using a Mechanistic Model

Summary: The curing kinetics of diglycidyl ether of bisphenol A (DGEBA) and 4,4′‐diaminodiphenylmethane (DDM) was analyzed using isothermal differential scanning calorimetry (DSC) modes by using a simple mechanistic model which includes two rate constants, k1 and k2, two reaction orders, n1 and n2, and the ratio of initial concentration of hydroxyl group to initial epoxy concentration, c0. Analyses of DSC data indicated that an autocatalytic reaction existed in the curing process. The mechanistic model proposed in this paper fits the experimental data exactly. Rate constants, k1 and k2 have been found to increase with rising curing temperature. The activation energies for the relative reactions were determined to be 66.00 ± 4.21 and 50.74 ± 8.92 kJ/mol, respectively. The complex equivalent constant, K, decreased with increasing temperature. Diffusion control was incorporated to describe the cure in the latter stages. Comparison of experimental data with the mechanistic model for the curing kinetics of DGEBA with DDM. magnified image Comparison of experimental data with the mechanistic model for the curing kinetics of DGEBA with DDM.