Coatings applications of thermosetting cure diagrams: off-stoichiometric high-T_g epoxy/amine systems

A reaction model for a high-T_g epoxy/amine system has been developed to describe both epoxy/amine and etherification reactions in kinetically-and diffusion-controlled reaction regimes. Calculations from the reaction model agree with experimental T_g versus time data for amine-rich and epoxy-rich mixtures using the one-to-one relationship between T_G and conversion. The time-temperature-transformation (TTT) isothermal cure diagram and the continuous heating-transformation (CHT) cure diagram are both calculated from the reaction model and are then applied to coatings operations. Optimization of coating processes and final material properties by exploiting gelation and/or vitrification during cure is discussed.