SBIR Phase II: Polyaniline Epoxy Primer with Related Topcoat: the Anticorrosion Coating System of a Barrier to Cations with a Barrier to Anions

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase II project is in bringing epoxy based conductive polymer anticorrosion paint system to the market. Corrosion will cost the US economy over $1 trillion in 2015. It is highly desirable to develop more effective anticorrosion technologies to reduce this huge economic cost of corrosion. The most effective anticorrosion pigments in use today are based on heavy metal pigments, such as chromates, lead compounds, and zinc/zinc compounds. Environmental, health, and safety concerns are driving the elimination of heavy metal pigments. The proposed new product will not only reduce toxicity introduced by current heavy-metal based anti-corrosion pigments, but also provide much improved corrosion protection. The project is especially targeting replacement of the epoxy based zinc-rich primer coating systems that are widely used on highway, marine, and energy infrastructures. Solving the poor processibility of environmentally friendly conductive polymers should enable open up a range of new applications beyond anti-corrosion coatings such as electrostatic dissipation, electromagnetic interference shielding, static resistant fibers, conductive inks, toners, and adhesives, etc. The intellectual merit of the proposed project lies in using advanced knowledge and understanding of anticorrosion coatings. It is generally assumed that organic coatings act as barriers to water and oxygen at the coating - environment interface. But corrosion of metals is an electrochemical reaction process that relates to both cations and anions. The present proposal suggests developing an ion barrier anticorrosion coating system: conductive polymer nanoparticle pigmented epoxy primer with a topcoat. The combination of the primer and topcoat constructs a barrier to both anions and cations, that inhibits the electrochemical corrosion reaction, therefore, provides efficient corrosion protection to the metal. This system will not use heavy metal anticorrosion pigments any more. If present proposed research succeeds, it will demonstrate how an ion barrier coating provides corrosion protection to a metal substrate, and how to formulate an ion barrier anticorrosion coating, and lead to the next generation of anticorrosion coating.