Modeling the Cure of an Epoxy‐Amine Resin with Bisphenol A as an External Catalyst

The cure kinetics of a DGEBF/DGEBA mixture with a commercial aliphatic amine mixture [poly(propylene) oxide diamine D230 and diethylene triamine (DETA)] was investigated by DSC. Two types of kinetic models based upon the formation of amine‐epoxy‐hydroxyl transition complex without or with fast pre‐equilibria have been tested and discussed. The mechanistic model with pre‐equilibria was based on the existence of two different epoxy‐hydroxyl complexes namely one involving hydroxyl groups of BPA and the other, the hydroxyl groups of polymer chains. All the kinetic and thermodynamic parameters have been evaluated and discussed. The results show that the mechanistic model with pre‐equilibria determined from isothermal cure provide a more reasonable fitting of the polymerization kinetics under programmed heating‐rate modes than Horie's model. Moreover, the former kinetic model allows the prediction of changes in the BPA content of the initial formulation with good accuracy. magnified image