Characterization of epoxy thermosetting systems by differential scanning calorimetry

Abstract

Abstract Differential Scanning Calorimetry (DSC) is used to study the curing behavior of epoxy systems. For non‐catalyzed diamine‐epoxy systems, the reaction enthalpy ΔH and the glass transition temperature T g are evaluated and related to the structure of the hardener. A method is developed to determine the activation energy. The effect of variations in the amine‐to‐epoxy ratio r on T g is also examined. A maximum value is observed for r = 1. Then, the influence of benzyldimethylamine as catalyst in an anhydride/DGEBA system and in three diamine/DGEBA systems is reported. In the cases of DDS and DDA curing agent the maximum value of T g is shifted, to r = 0, 6. The results are explained by different reaction mechanisms.