Multifunctional Environmentally Friendly Inhibitors and Coating Adhesion Promoters

When a metal surface is prepared for recoating/painting, the surface is cleaned in some manner. The cleaned surfaces are then exposed to humid environments for some time before recoating and can undergo corrosion. For example, mild steels undergo flash rusting. Also, surfaces are often contaminated with salt and other seawater-related residues which contribute to premature coating failures. Inhibitors have been shown to provide significant levels of corrosion protection when designed for particular applications and uses.  However, to date, compounds added to abrasive media or applied following surface preparation of metals prior to painting result in no more benefit than water washing while the more effective additions are hazardous to workers and the environment.  A non-toxic, environmentally friendly inhibitor that protects the surface from corrosion during and surface preparation and increases the adhesion of the final coating would result in significant savings in maintenance budgets as well as meet safety and environmental compliance standards. The goal of this research was to develop a new class of non-toxic, multifunctional, environmentally friendly corrosion inhibitors and coating adhesion promoters. This research involved isolation of biological polymers from two marine organisms (the blue mussel, Mytilus edulis and the sea squirt, Molgula manhattensis) and determining the effects of the polymers on the corrosion resistance of metals as well as their ability to promote adhesion of coatings.  Characterization of the isolated proteins involved amino acid composition and polyacrylamide gel electrophoresis (PAGE). The results of electrochemical testing (polarization curves and impedance spectroscopy results) and cabinet testing for treated and untreated steel samples will be reported and discussed.