Vitrification and Devitrification during the Non‐Isothermal Cure of a Thermoset. Theoretical Model and Comparison with Calorimetric Experiments

Abstract

AbstractThe processes of vitrification and devitrification that occur during the non‐isothermal cure of a cross‐linking system are studied in terms of their dependence on frequency. Experimental results are obtained by TOPEM, a new multi‐frequency temperature modulated differential scanning calorimetry (TMDSC) technique, and a simulation with MATLAB was used to model the vitrification and devitrification times as a function of the frequency and heating rate. Simulations were made for five different velocities of scan. Other parameters, such as the exponents in the Kamal equation, λ in the DiBenedetto equation, and the activation energy for the frequency dependence of Tg, were also considered. The experimental and simulated results were found to be in good agreement and some advantages of the TOPEM technique are discussed.magnified image