Anticorrosion hybrid nanocomposite coatings with encapsulated organic corrosion inhibitors

The development of effective anticorrosion pretreatments for metallic substrates is an issue of great importance for durability of metal structures and components. In this work for improved corrosion protection properties of sol–gel derived hybrid coatings, encapsulated corrosion inhibitors [2-mercaptobenzothiazole (MBT) and 2-mercaptobenzimidazole (MBI)] in the presence of β-cyclodextrin (β-CD) have been incorporated into hybrid coatings. Inclusion complex formation of MBI or MBT with β-CD led to encapsulated corrosion inhibitors which became active in corrosive electrolytes, and could slowly diffuse out of the host material to ensure continuous delivery of the inhibitors to corrosion sites and long-term corrosion protection. Structural characterization of the hybrid coatings were performed using EIS, SEM coupled with EDX, and FTIR.