Model-fitting and model-free nonisothermal curing kinetics of epoxy resin with a low-volatile five-armed starlike aliphatic polyamine

Abstract

This paper reports the original work on the nonisothermal curing reaction of bisphenol A epoxy resin (DGEBA) and N,N,N′,N′,N′′-penta(3-aminopropyl)-diethylenetriamine (PADT). The nonisothermal reaction kinetics of DGEBA/PADT is systematically investigated using dynamic DSC with the model-fitting and advanced model-free isoconversional methods. The high reaction heats (115–118kJ/mol) indicate that PADT can efficiently cure DGEBA, and the reaction activation energy is 55.4kJ/mol. The further reaction kinetic analysis with the Málek method discloses the autocatalytic characteristic, and the Šesták–Berggren model is able to well simulate the reaction rate. Furthermore, the dependence of the effective activation energy on conversion is established from the model-free kinetic analysis with the Vyazovkin method, from which the reaction mechanisms are discussed in detail. Additionally, the isothermal conversion predication from the nonisothermal data is accomplished using the two methods, respectively, with an acceptable match obtained.