Aqueous phase polymeric corrosion inhibitors: Recent advancements and future opportunities

• Binding and anticorrosive effect of aqueous phase polymeric corrosion inhibitors is surveyed. • Polymers adsorb strongly through bonding and provide excellent surface coverage. • Polar substituents enhance the inhibition potential as well as bonding capabilities of the polymers. • Polymeric corrosion inhibitors act as mixed- and interface-type corrosion inhibitors. • Based on literature outcomes, corrosion inhibition mechanism using polymers has also been presented. The use of heterocyclic compounds is established as one of the most successful, economic and practical techniques of corrosion protection. The heterocyclic compounds develop into useful by adsorbing at the metal-environment interface using their electron dense centers, called adsorption centers. However, because of their relatively smaller size, they provide insufficient surface protection. More so, their synthesis is connected with the use of expensive and toxic chemicals, solvents and catalysts. Therefore, there is an extreme demand of ecofriendly alternatives of relatively bigger molecular size. In this direction, the use of natural and synthetic polymers as anticorrosive materials is gaining particular attention. Due to their polymeric nature and presence of polar functional groups at the periphery, the polymers effectively adsorb on the metallic surface and provide excellent surface protection. More so, the exercise of natural polymeric alternatives including carbohydrates, proteins and their derivatives offers a new alternative path to replace traditional toxic corrosion inhibitors. The present review paper aims to collect outcomes of major reports describing the corrosion inhibition potential of natural and synthetic polymers. Advantages of polymers over traditional corrosion inhibitors and the mechanism of corrosion inhibition using polymers have also been discussed.