Isothermal Cure of Bisphenol Epoxy Resin with a Nonlinear Aliphatic Polyamine Hardener

An amine terminated polypropylenimine dendrimer (DAB-dendri-(NH2)4), was employed as a new nonlinear aliphatic curing agent for diglycidyl ether of bisphenol A (DGEBA). Isothermal curing reaction kinetics of DGEBA/DAB was investigated with a differential scanning calorimeter (DSC). The autocatalytic model proposed by Kamal was demonstrated for simulating the reaction kinetic in the initial stage of the cure. It was found that the overall reaction order, m + n, was in the range 2.3688–2.5980. The rate constants of k l and k 2, showed a good Arrhenius fit to temperature and the associated activation energies was estimated to be 60.41 kJ/mol and 55.66 kJ/mol, which showed in agreement with values reported for common epoxy-amine systems. In the latter stage of curing, diffusion control was considered and a diffusion factor was incorporated into the autocatalytic model; therefore, it was possible to accurately predict the cure kinetics over the whole range of conversion.