Blistering of Marine Anticorrosive Epoxy Polyamide Coatings

Abstract

Abstract Paint blistering, although not a paint failure, is an indication of processes occurring beneath the film that may lead to eventual failure. A marine epoxy polyamide paint used on ship's underwater hulls appeared to blister more after a formulation change. The original and modified formulations were tested for blistering tendency using a newly developed hot-water immersion test. Other commercial epoxy formulations and the effects of varying raw material supplier and paint manufacturer were also evaluated. The results showed that a) the modified formulation blistered more than the original formulation b) the commercial proprietary formulations were not superior to the formulation now used, and c) variation of raw material suppliers and paint manufacturer had an effect blister performance.