Abstrato

Curing kinetics of an epoxy-acid copolymer systems. Effect of mineral filler (CaCO3)

F.Heba, M.Mouzali, M.J.M.Abadie

The effect of introducing a mineral filler (CaCO3) on a commercial epoxy resin (DGEBA) cured with high molecular weight acid copolymers, on the kinetics properties has been studied by using differential scanning calorimetry (DSC).The kinetics propertieswere determined at different content of CaCO3 in the systems. The enthalpy of the reaction (H), the gel temperature (Tg), the temperature at the maximum peak (Tmax) and the temperature at the final conversion (Tf) were obtained from DSC curves which were also used for kinetic calculations. The activation energy of cross linking reactionswas calculated by the Freeman – Carrol relation. Only modest effects has been observed on Tg and Tmax parameters to 80-90%byweight of CaCO3, whereas, an important decrease of Tf is observed from 10 % of CaCO3 content. The effect of the calcium carbonate on curing parameters is very low to 50 % of CaCO3 content, above this amount, the heat of curing (H) decreasedwhereas, the activation energy (E) and the reaction order (n) increased.