Corrosion is the foremost reason for the deterioration of metallic components used in harsh environments and hence research on the development of an innovative protective system with admirable performance has become a subject of leading importance. Currently, chromates free organic or the polymer coatings on the metal substrate bestow an efficient barrier amongst the metal and inhibit corrosion and save the environment. Researchers have involved in the development of polymer coating containing nanoparticles because reinforcement of nanoparticles decreases the porosity and provides a zig-zag diffusion path which in turn forms barrier layer on the metal surface to protect the metal from the harmful corrosive species. This present chapter deliberates the application of polymer-based nanocomposite coating to mitigate the corrosion of metals against harsh environment. This chapter covers the utilization of carbon-based nanoparticles, inorganic nanoparticle, conductive polymer, self-heling polymer, etc., and could shows a new insight to for anti-corrosive metal surface protective coating.
TopIntroduction
Currently, corrosion of metals has been becoming a prime problem which extremely spoils the industry with a financial loss and creates an enormous risk to human beings. Because, corrosion cannot be completely prohibited and it’s simply obstructed and reduced. Therefore, it is high time to protect the metal from corrosion to minimize economic losses. Steel is extensively utilized materials in various application fields, for example, civil engineering, military, transportation, gas and oil industry owing to its excellent mechanical properties and comparatively lower cost contrasted to advanced alloy materials (El Rayes et al., 2013). Corresponding to the published report of the World Steel Association in October 2017, the world utilization quantity to 145.3 million tonnes (mt) in 2017 with an enhanced of 5.9% evaluated in the year 2016 (World Steel Association et al., 2017). On the other hand, lots of the critical issues of steel arises due to its corrosion, reduction, particularly in marine environments that characteristically have higher salinity and humidity, these two factors influence the steel mechanical performance. An approximated 20% of world steel production is lost every year in the form of rust (Bhandari et al., 2015). Every nation is spending 1-5% gross national product (GNP) on corrosion issues (Koch et al., 2002). In the evaluations of the World Corrosion Organization (WCO) the yearly cost of approximately $2.4 trillion expenditure worldwide (Natesan et al., 2005). For that reason, to inhibit the mechanical properties of the steels via applying nanocomposites organic coatings to the substrate and improved the product life and reduce the maintenance cost. Then, diffusion of the H2O molecules through the anticorrosive polymer nanocomposite coatings is recognized as the main contributor to decrease the corrosion, delamination and adhesion in the coatings, which accordingly leads to common coating substitute and notable maintenance costs (Melchers et al., 2008).
Numerous, corrosion approaches are presently accessible like the employ of coatings, corrosion inhibitors, surface treatment, and electrochemical cathodic protection (Chen et al., 2007; Song, 2005; Solmaz et al., 2008; Yun et al., 2007). Amongst all, the utilization of corrosion protection coating is attracting to the overall market interest due to the suitable fabrication and excellent corrosion protection properties (Low et al., 2006; Wang et al., 2009; Gray et al., 2002).
Currently, nanocomposite coatings have attracted a great interest and rapidly developing approaches for scheming and fabrication of durable anticorrosive surface coatings with superior properties. A nanoparticle exhibits high surface area to volume ratio and provides a torturous path for the diffusion of H2O molecule which leads to better surface protection as compared to bulk materials. The nano materials obtained higher barrier properties to the conventional fillers. Several nanoparticles-based coatings have been reported such as TiO2 (Shi et al., 2002; Liu et al., 2018), Al2O3 (Golru et al., 2014; Dhoke et al., 2012), SiO2 (Bakhshandeh et al., 2014; Palraj et al., 2015), ZnO (Ramezanzadeh et al., 2011; Sonawane et al., 2010), Fe2O3 (Dhoke et al., 2009; Palimi et al., 2015) etc. The fabrication of polymer nanocomposite coatings to protect steel substrates from the corrosion seems to be a fascinating solution. Figure 1 demonstrated the application of polymer nanocomposites coating surfaces in various fields.
Figure 1. Polymer nanocoatings coating application in various fields