Polyaniline and poly(m-toluidine) prepared by inverse emulsion pathway as corrosion inhibitors in surface coatings

Purpose - The purpose of the paper is to examine the synthesis of polyaniline (PAn) and poly(m-toluidine) (PmT) via an inverse emulsion polymerisation pathway and evaluate of the synthesised polymers as corrosion inhibitors for steel protection in surface coatings. Design/methodology/approach - PAn and PmT were prepared by inverse emulsion polymerisation using ammonium persulphate as an initiator and sodium dodecylbenzene sulphonate (SDBS) as an emulsifier. Spectrophotometric measurements were conducted to characterise the prepared polymers. Latex paint formulations were prepared and dry paint films were evaluated for their physical, mechanical and corrosion protection performance. Findings - The prepared conducting polymers of PAn and PmT are good candidates for enhancing the corrosion protection of steel. They showed good performance as corrosion inhibitors in latex paints without bad side effects on the physico-mechanical properties of paint films. Practical implications - Recent advances in corrosion protection of steel by coatings via inverse emulsion polymerisation of aniline and m-toluidine have improved performance of anti-corrosive water-borne paints. Using formulations based on this new technology, offer uncompromised high performance eco-friendly anti-corrosive water-borne systems that answer the future industrial demands from the economical and environmental points of view. Originality/value - PAn and PmT prepared by inverse emulsion polymerisation showed promising results as corrosion inhibitors for steel protection. The polymerisation process was conducted in water (emulsion polymerisation) and the polymer lattices were incorporated in water borne paints from ecological and economical points of view.