Kinetic model for the curing reaction of a tetraglycidyl diamino diphenyl methane/diamino diphenyl sulfone (TGDDM/DDS) epoxy resin system

Abstract

Abstract A kinetic model based on reaction mechanisms was proposed for the description of the curing behavior of a TGDDM/DDS resin system. The characteristic of this model is the separation of the non‐autocatalytic part from the autocatalytic part of the reaction, so the model can match the well‐established pseudo second order reaction mechanism, as proposed by many other studies about the epoxide/amine reaction. The present model was compared with two other widely used models for the autocatalytic curing behavior of epoxide/amine system, i.e., an equation based on a single rate constant and another based on pure phenomenological analysis, by using DSC data. It was found that the reaction rate calculated from this new model can fit the DSC empirical result much better than those calculated from the other two models. Parallel studies on some other resins, such as the DGEBA/m‐PDA system, also proved the superiority of this kinetic model. Results have revealed that the new model was valid for most of the epoxide/1 o ‐amine systems studied. A discrepancy did appear as the epoxide/amine molar ratio and/or the isothermal curing temperature reached certain limits, owing to the occurrence of side reactions.