Rheological monitoring of curing reaction of an epoxy system: effect of heating rate

In this work, we present a rheological study of the non-isothermal curing r eaction of an epoxy resin, diglycidyl ether of bisphenol A, with aliphatic amines of different functionalities. The reaction was carried out under a l inear temperature program and the epoxy-amine mixtures were prepared at dif ferent epoxy groups to amine-hydrogen ratios The effect of vitrification on the curing reaction is analyzed as a function of the healing rate. At low heating rates, the viscous modulus, G ", presents two peaks. The first peak is due to the vitrification-devitrification phenomenon that takes place du ring cure. At the second peak, the sample is completely cured and the decre ment is G " is only due to the temperature increment.