Surface electroanalytical approaches to organic polymeric coatings

Abstract

AbstractSurface characterization techniques for organic polymeric coatings are numerous and diverse. Many of these techniques can provide physical information about how coating systems perform under certain environmental conditions, but they provide less mechanistic information on how they function as corrosion barriers. Since many coating failures are initiated from ionic diffusion through the coating and the subsequent reactivity at the coating–metal interface is mostly electrochemical in nature, the utility of electrochemical‐based techniques is therefore more appropriate. This mini‐review highlights five of the most commonly used electroanalytical techniques for the evaluation of corrosion protection properties for polymer coatings on metals: open circuit potential, electrochemical impedance spectroscopy, potentiodynamic polarization, electrochemical noise and scanning electrochemical microscopy. These techniques can perform their own unique approach of examining the protection performance of polymer coatings, but the elucidation of coating degradation and mechanism of corrosion at the coating–metal interface is their common objective. © 2020 Society of Industrial Chemistry