SBIR Phase I: An Approach to Pigments that Provide Corrosion Protection on-Demand

This Small Business Innovation Research Phase I project addresses the important problem of replacing anti-corrosion chromate-based pigments in primers for metals. We will mimic the properties of chromate in two novel, on-demand pigments, both added to a primer. The primer will then provide corrosion resistance to several metals such as steel, galvanized steel and aluminum alloys and also protection of defects in the coating due to its slow-release effect. One pigment will consist of an inorganic particle whose surface is a cation exchanger. We will attach corrosion-inhibiting cations to it. The other pigment is an inorganic particle whose surface is an anion exchanger. We will attach corrosion-inhibiting anions to it. When an electrolyte enters the coating, the pigments will release various ions, which are effective in protecting corrosion of aluminum and galvanized steel. When plain water enters the coating, the pigments will remain dormant, i.e., they provide corrosion protection on-demand only. This project will be executed in collaboration with the University of Cincinnati, where more complex ion exchangers will be synthesized and tested. The broader impact/commercial potential of this project is in a new coating technology that is environmentally friendly. The new material will also be flexible, in that we can tailor the four components to a particular metal substrate and primer. As a result, potential customers for this technology will be numerous. Examples are the automotive industry (for car repair finishes, and the painting line in automobile manufacturing plants), wash primers for repair and touch-up, the shipbuilding industry, the aerospace industry (coatings for aircraft), the coil coating (steel) industry, and many others. Combined, these markets represent a commercial opportunity of at least $5 billion. The societal impact will be that workers in paint-manufacturing plants will no longer be exposed to hazardous chromate-containing materials. This project will also enhance our scientific understanding of the mechanisms by which coatings protect metals and how anti-corrosion pigments work in such systems. In particular, the relationship between the hydrophilicity of the coating and the water-solubility of the pigment will be elucidated in this project. The mechanism by which certain inhibitors protect metals is another focus of our study.