Kinetic and thermodynamic studies of an epoxy system diglycidyl ether of bisphenol A/1, 2 diamine cyclohexane/calcium carbonate filler

The curing reaction of an epoxy system consisting of a diglycidyl ether of bisphenol A (BADGE n = 0) and 1,2-diaminecyclohexane (DCH) with a calcium c arbonate filler was studied by differential scanning calorimetry (DSC) and using a scanning electronic microscope (SEM). As a first stage, the optimum content of the filler determined was 20%. From a kinetic study, in which t wo models were used, parameters such as reaction orders, rate constants, an d activation energies were determined. A thermodynamic study allowed calcul ation of enthalpy (Delta H#), entropy (Delta S#), and free-energy ((Delta G #) changes. The results were compared to those obtained for the same epoxy systems without the filler. (C) 2000 John Wiley & Sons, Inc.