Curing kinetics study of epoxy resin/flexible amine toughness systems by dynamic and isothermal DSC

Curing kinetics of two epoxy resin/flexible amine systems was studied by dynamic and isothermal differential scanning calorimetry (DSC). In dynamic experiments, the activation energy at different curing degree was computed under nonisothermal condition by using isoconversion method. At the same time, the isothermal experimental data was simulated by nonlinear least-squares fitting (NLSF). The results showed that the Arrhenius activation energy (E) increased with the increasing curing degree of diglycidyl ether of bisphenol A (DGEBA)–Jeffamine (T403) system, while in the DGEBA–D230 system activation energy decreased in the initial stage, and then increased when the value of α (the curing degree) was within the range of 0.1–0.4, and afterwards decreased. Under the isothermal condition, the Kamal's model was suitable to simulate two systems in the whole curing process.