Smart Coatings in Anti-corrosion Applications: Types and Corrosion Protection Mechanisms

Authors

Department of Material Science and Engineering, Shahid Chamran University

Abstract

Doping corrosion inhibitor in a host structure (container) draws much attention among the researchers. This system, called smart corrosion inhibition, is designed not only to avoid undesirable reactions between the corrosion inhibitor and the matrix but also letting the inhibitor to be consumed just where it is needed. Moreover, in some cases, this system can undergo self-healing properties, if the coating is scratched. A lot of strategies are suggested to achieve these purposes, including loading corrosion inhibitor in nano-micro capsules, doping corrosion inhibitor in porous containers and etc. Other reservoirs that can be loaded with corrosion inhibitor are nanotubes, ion exchange particles, conductive materials, layer by layer polyelectrolytes, and porous materials. For instance, multi-layer polyelectrolytes can be used to immobilize the corrosion inhibitor. Changing the system conditions can cause polyelectrolytes to weaken, and letting the corrosion inhibitor release. In general, an ion exchange occurs between corrosive ions and inhibitors in the system, or the inhibitor is released due to local pH changes, or as a long-term diffusion, the inhibitor can avoid corrosion reaction. Therefore, some changes are needed in the system to commence smart corrosion inhibition process.

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