Chromate-Free Nanoparticle Corrosion Inhibitors for Steel

The corrosion of steel has widespread economic and environmental effects, and the annual cost of corrosion exceeds $275 billion. About 49% of U.S. steel production goes to replace corrodded matal parts and consumer goods. Corrosion also has a significant impact on the environment. Structures such as storage tanks, pipelines, ships, railcars, and tanker trucks, which store and/or transport hazardous materials are frequently damaged by corrosion and leak their contents inot the environment. For example, corrosionis the leading caure of leaking storage tanks, which in turn threatens public health and leads to billions of dollars in direct and indirect environmental costs. Chromate-load organic coatings are the most effective method of preventing corrosion of metals such as steel. Unfortunatey, hexavalent chromate corrosion inhibitors produce their own environmental problems, and their toxic properties are well documented. the use of chromate-inhibited spray-on coatings produce chromate containing leachates and inhalable chromate tainted dusts. Furthermore, the removal of chromate-inhibiting coatings by chemical or mechanical means also generates hazardous chromated waste. Because hexavalent chromates are known carcinogens, their use and disposal is strictly regulated. In fact, in much of the developed world, their use and disposal are being banned outright. Better technologies are clearly of economic, public health and environmental importance. In this Phase I proposal TDA Research, Inc. (TDA) proposes to develop a chromate-fress corrosion inhibitiong nanoparticle additve for steel. These nanoparticles will have effective organic corrosion inhibitors anchored to the surface that are triggered to release by the corrosion process. While anchored, the corrosion inhibitores are non-leachable, but when released they migrate to arrest corrosion at the metal surfaces. The use of the triggered release from the nanopaticle platform reduces leaching of the corrosion inhibitor out of the coating and into the environment and increases the effectivenes th lifecycle of coating. There is a large market for protective corroion inhibiting coatings, roughly $6.7 billin per year in ghre U.S. A chromate-free corosion coating for steel could be used for a range of applications, includkng automotive, aerospace, bridges, buildings, and military.