Coatings for Corrosion Inhibition
According to a recent review by Thompson, Yunovich, and Dunmire (Corrosion Reviews, vol. 25, pages 247-261, 2007), corrosion costs the U.S. economy approximately $276 billion annually. Due to the enormous impact of corrosion on our economy, there exists a continuing need for more effective, lower cost methods to inhibit metal corrosion. The coating of metals such as steel and aluminum with polymer coatings has been widely used for inhibiting corrosion. The effectiveness of a polymer coating for a given application depends on the interplay of several variables such as the barrier properties of the polymeric binder, the adhesion of the coating to the substrate in the application environment, coating durability, and the activity of corrosion inhibiting additives.
The Combinatorial Materials Research Laboratory at NDSU has been heavily engaged in the development of new highly-effective, environmentally-friendly coatings for corrosion control using combinatorial/high-throughput methods. Key components of the combinatorial workflow that have enabled the rapid development of coatings for corrosion control include a highly capable coating formulation system that provides for high shear dispersion of pigments and corrosion inhibitors as well as aspiration and dispensing of high viscosity polymers, an automated, parallel electrochemical measurement system for rapidly screening the capability of coatings to provide corrosion protection, and a semi-automated pull-off adhesion system for rapidly screening coating adhesion. Several publications are available that describe in detail the combinatorial workflow as well as individual components of the workflow.
Currently, a large effort sponsored by the Air Force Research Laboratory is being undertaken to develop new environmentally-friendly coatings for aircraft. This program, entitled “Durable Hybrid Coatings for Aircraft,” has resulted in the development of new environmentally-friendly primers for aluminum alloys. The novel primers utilize surface passivated magnesium particles dispersed in a polymeric, inorganic, or hybrid organic-inorganic binder system to provide galvanic protection of the substrate.
Dr. Bret Chisholm
Senior Research Scientist and Director, Combinatorial Materials Research Laboratory
NDSU Center for Nanoscale Science and Engineering