COATINGS APPLICATIONS OF THERMOSETTING CURE DIAGRAMS - OFF-STOICHIOMETRIC HIGH-TG 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 kinetica lly- 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 betwee n T(g) and conversion. The time-temperature-transformation (TTT) isoth ermal cure diagram and the continuous heating-transformation (CHT) cur e diagram are both calculated from the reaction model and are then app lied to coatings operations. Optimization of coating processes and fin al material properties by exploiting gelation and/or vitrification dur ing cure is discussed.