Nanocomposite organic coatings for corrosion protection of metals: A review of recent advances

Various methods have been employed to protect metals in assets from corrosion damage, among which is the use of very efficient and economical organic coatings. The performance of organic coatings is often influenced by their inherent porosity, which provides pathways for corrosive species or results in vulnerability to mechanical damage. Nanomaterials (NMs) have a wide range of shapes and sizes that have been employed to improve the engineering performance of coatings. They have been shown to increase corrosion resistance and other properties of coatings through various mechanisms, some of which are not well known. Following an overview of the different types of anticorrosion coatings and their protective mechanisms in this article, we summarized the effects of different NMs on the performance of polymer-based coatings. It was observed that bio- and carbon-based nanomaterials are the most promising nanofillers to improve the barrier performance of organic coatings. Smart nanocomposite organic coatings were then examined, as they could be regulated to release repairing or protective agents, mainly to corrosion defects or damaged areas of the coating once triggered by external stimuli. Then, high-performance nanocomposite organic coatings, which provide long-lasting and superior corrosion protection, were examined. Subsequently, advanced characterization methods for studying nanocomposite organic coatings were briefly discussed. We concluded with a summary of the key findings and the research needs.