Curing Kinetics of a Bisphenol-F Epoxy Resin and Succinic Anhydride System

Abstract

The kinetics of the cure reaction for the system of bisphenol-F epoxy resin (BPFER) with succinic anhydride (SA) as a curing agent was investigated with a differential scanning calorimeter (DSC). Autocatalytic behaviour was shown in the first stages of the cure for this system, which was well described by the model proposed by Kamal that includes two rate constants, k₁ and k₂, and two reaction orders, m and n. The overall reaction order, m + n, is in the range 2.1–2.6, and the activation energies for k₁ and k₂ are 89.1 and 68.8 kJ mol⁻¹, respectively. In the later stages, a crosslinked network is formed and the cure reaction is mainly controlled by diffusion. A diffusion factor, f(α), was introduced into Kamal's equation and the calculated values agree very well with the experimental data. Cure was accelerated by a tertiary amine.