Development of high performance,waterborne coatings. Part III: Characterization of coatings and cured film

High performance waterborne coatings were developed which could be utilized as an adhesive primer for sideseam bonded cans. The manufacturing process is unique; blending an epoxy / phenolic solution and an acrylic resin solution and dispersing the mixture in an aqueous medium by the phase transition method. The epoxy resins are neither chemically modified by grafting nor esterified by acrylic resin, which is thought to develop the excellent performance of epoxy / phenolic coatings. The morphology of the coatings and cured film was characterized and found to be quite different from the conventional waterborne coatings, i.e., the acrylic-modified epoxy resin systems. It was confirmed that acrylics and epoxy / phenolic resins exist in separate phases in the cured film, and that the epoxy / phenolic resin constitutes the continuous phase.