Enthalpic, entropic, and square gradient contributions to the surface energetics of amine-cured epoxy systems.

The evolution of surface tension during polymerization of three amine-cured epoxy systems was investigated. Due to the chemical reaction of the epoxy groups with primary and secondary amines, the energetic status of an epoxy-amine system increased during polymerization. At the same time, the polymerization process induced entropic variations, also contributing to the evolution of surface energetics.