Curing kinetics study of epoxy resin/hyperbranched poly(amideamine)s system by non-isothermal and isothermal DSC

Abstract

AbstractCuring kinetics of epoxy resin/hyperbranched poly(amide amine)s (HPAMAM) system was studied by non-isothermal and isothermal differential scanning calorimetry (DSC). Non-isothermal DSC scans indicated that H-PAMAM was an effective curing agent of epoxy resin. The apparent activation energy (E) was 54.3 kJ/mol calculated through Kissinger method, and the kinetic parameters were determined by Málek method for the kinetic analysis of the thermal treatment obtained by DSC measurement. A two-parameter (m, n) autocatalytic model (Sěsták-Berggren equation) was found to be the most adequate selected kinetic model. In addition, the predicted curves from the kinetic model fit well with the nonisothermal DSC thermogram. The isothermal DSC method was used to investigate the curing process for resin at 60, 65, 70, 75 and 80 °С, respectively. Isothermal kinetic parameters, including k1, k2, m and n, were determined based on an autocatalytic mechanism proposed by Kamal. Both models were validated for a fitting to the experimental data by the Levenberg-Marquardt method. A process to determine the initial values for the fitting procedure was also proposed. The predictions of the validated models were in good agreement with the measured data, and were therefore applicable for numerical process optimization