Comparison of the Curing Kinetics of the RTM6 Epoxy Resin System Using Differential Scanning Calorimetry and a Microwave-Heated Calorimeter

The cure of a commercial epoxy resin system, RTM6, was investigated using a conventional differential scanning calorimeter and a microwave-heated calorimeter. Two curing methods, dynamic and isothermal, were carried out and the degree of cure and the reaction rates were compared. Several kinetics models ranging from a simple nth order model to more complicated models comprising nth order and autocatalytic kinetics models were used to describe the curing processes. The results showed that the resin cured isothermally showed similar cure times and final degree of cure using both conventional and microwave heating methods, suggesting similar curing mechanisms using both heating methods. The dynamic curing data were, however, different using two heating methods, possibly suggesting different curing mechanisms. Near-infrared spectroscopy showed that in the dynamic curing of RTM6 using microwave heating, the epoxy-amine reaction proceeded more rapidly than did the epoxy-hydroxyl reaction. This was not the case during conventional curing of this resin