The Waterborne Symposium 2025

Co-Authors: Franklin Leal, and Dan Weinmann

Abstract

Epoxy resins have been used for decades in applications demanding excellent adhesion and corrosion resistance, but historically have not been suitable for coatings where ultraviolet (UV) resistance is needed. A direct-to-metal coating, comprised of a novel modified cycloaliphatic epoxy resin combined with a lower yellowing amine curing agent, was designed to deliver superior performance in corrosion resistance and adhesion. Additionally, this epoxy resin system offers improved gloss retention and color stability compared to standard epoxy coatings. Both the resin and curing agent are optimized to minimize dry time while maximizing hardness development. The relationship between epoxy-amine stoichiometry and coating performance was evaluated to further improve the system. Comparative testing with a commercially available epoxy-polyamide DTM coating showed that the novel epoxy system performs well against the competitive material while significantly improving the UV resistance, as determined by gloss and color retention.
.