Corrosion Protection by Intrinsically Conducting Polymers

For a couple of years now there has been an ongoing discussion about how effective ICPs are in corrosion protection. The first argument to consider electrochemically prepared thin films of ICPs as corrosion protective coatings came from the positive value of the redox potential of these materials. The surface can be expected to be noble if the substrate 

A second attempt to explain the corrosion protection of polyanUine was the formulation of a mechanism with a catalytic reduction of oxygen and a simultaneous formation of a passivating metal oxide film on the substrate. Later it was shown that this mechanism is not supported by experimental investigations.  

Obviously, there are still many open questions about the corrosion protective properties ofICPs. 

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Mechanism of Corrosion Protection by Intrinsically Conducting Polymers... 

Rammelt, U., P.T. Nguyen, and W. Plieth. 2001. Corrosion protection by films of intrinsically conducting polymers. Proceedings of Electrochemical Society 2001-22 (Corrosion and Corrosion Protection), 604. 

Figure 16.6 Galvanic coupling between iron disc (0.25 mm diameter) and PPy-coated iron ring (5 mm outer diameter) immersed in 0.1 M K2SO4 solution (pH 4). The gap between the disc and the ring is 75 pm. (Reprinted with permission from Journal of Electroanalytical Chemistry, Mechanism for protection of iron corrosion by an intrinsically electronic conducting polymer by T.D. Nguyen, T.A. Nguyen, M.C. Pham etai, 572, 2, 225-234. Copyright (2004) Elsevier Ltd)...

Nguyen, T.D., et al. 2004. Mechanism for protection of iron corrosion by an intrinsically electronic conducting polymer. / Electroanal Chem 572 (2) 225. 

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