Self-healing anticorrosive coatings

The paper is devoted to development of novel approach to dope coatings with active anticorrosion species with self-healing ability. They contain nanoreservoirs which can store active agents and provide controllable release of them. The titania nanoparticles doped with cerium ions and organic inhibitors were used as nanocontainers to dope the hybrid sol-gel matrix and to provide long-term corrosion protection. 

Nesterova, T., Dam-Johansen, K., and Kill, S. Synthesis of durable microcapsules for self-healing anticorrosive coatings a comparison of selected methods. Progress in Oiganic Coatings, 70(4), 342-352 (2011). 

Zheludkevich, M. L., Shchukin, D. G., Yasakau, K. A., Mohwald, H., and Mario, G. S. Anticorrosion coatings with self-healing effect based on nanocontainers impregnated with corrosion inhibitor. Chemistry of Materials, 19(3), 402 11 (2007). 

Gonzalez-Garcia, Y., Garcia, S.I, Hughes, A.E. and Mol, IM.C. (2011), A combined redox-competition and negative-feedback SECM study of self-healing anticorrosive coatings, Electrochem. Comm., 13,1094-1097. 

Nesterova T. (2012), Self-healing anticorrosive coatings, PhD thesis. Technical University of Denmark, Denmark. 

Novel and self-healing anticorrosion coatings using rare earth compounds... 

Sauvant-Moynot V, Gonzalez S., Kittel J. (2008), Self-healing coatings An alternative route for anticorrosion protection , Prog. Org. Coat, 63, 307. 

Zheludkevich M.L., Ferreira M.G.S (2011) Ch. 2 Self-healing anticorrosion coatings in Self-healing properties of new surface treatments, L. Fedrizzi (Ed.), EFC Publications, Maney Materials Science, Leeds, UK. 

Several approaches have been reported by Hu and coworkers to further improve the anticorrosion performance of electrodeposited silane sol—gel films. They found that adding proper concentration of nitrate ions into the silane deposition solution facilitated the electrodeposition process by reducing nitrate to nitrite, and thus enhanced the corrosion resistance of the films obtained [31]. Co-electrodeposition of silane with silica or titania nanoparticles [47,49], or Ce (N03)s [77], ako improved the films anticorrosion performance. Small content of nanoparticles was foimd to increase the compactness of the electrodeposited silane films. Ce(III) provided a self-healing effect for long-term immersion of the dip-coated Ce(III)-doped bis(triethoxysilylpropyl) tetrasulfide (BTSPS) films in... 

The anticorrosion performance of these coatings assessed by electrochemical impedance spectroscopy shows that the lower impedance was obtained when BTA was directly added to the sol-gel matrix, whereas the best performance was achieved with inhibitor-doped TiO coated with a hybrid film. In terms of active corrosion protection, there is a periodic decrease/increase of impedance associated with the breakdown followed by the self-healing of the intermediate oxide layer. SVET was employed to study the self-healing ability of bi-layer systems at the micro level. The measurements of local corrosion current evolution in the zones of artificial defects have demonstrated well-defined corrosion activity on the sirrface of AA2024 coated with sol-gel film only, while no corrosion activity was revealed even after 24 hours on the alloy treated with a bi-layer system. The reported resirlts show that the adsorbed inhibitor is leached out from the porous... 

Zheludkevich M. L. (2008), Self-healing anticorrosion coatings , in Ghosh S. K., Self-healing materials, Wiley-VCH, 101 0. 

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