Studies on Greener Anticorrosive Coating to Steel Rebars with Waterborne Polyurethane Binders

Corrosion of steel in concrete is a natural phenomenon causing severe distress to structures situated in areas with high humidity, sea coasts, high salinity, etc. This menace can destroy even the strongest buildings, bridges, ports, dams, plants, runways, etc. Various surface coatings are in practice for protecting the steel reinforcing bars from corrosion. However, the available coatings are solvent based and hence toxic and pollute the atmosphere. This paper deals with the formulation of suitable greener protective anticorrosive coating to steel rebars in order to enhance the corrosion resistance and protect the rebars. Fifteen polyurethane-based coatings with suitable functional pigments, fillers, corrosion inhibitor and hiding agent (titanium dioxide) were developed and their properties on resistance to corrosion were studied and the results are presented.