Cure kinetics, gelation, and glass transition of a bisphenol F epoxide

Phenomenological cure kinetic relations for a commercially available amine‐cured epoxy were developed independently using differential scanning calorimetry (DSC) in isothermal and dynamic (constant heating rate) modes and using numerical optimization techniques. The resulting model was found to be independent of the method used to collect reaction rate data. The model was modified at high temperature to account for an observed deviation from Arrhenius behavior. The cure dependence of the glass transition of the material was also investigated with DSC. The gel point as measured by parallel plate rheometry was found to occur at a degree of cure of 0.71, a value significantly advanced from a simple Flory prediction based on the functionality of the cross‐linking agent.