Comparative study of effect of corrosion on mild steel with waterborne polyurethane dispersion containing graphene oxide versus carbon black nanocomposites

Abstract

Recently developed strategies for graphene oxide and carbon black nanocomposites have enabled production of robust waterborne polymer nanocomposites with enhanced nanoparticle dispersion and barrier protection performance. In this article, we have presented processing, morphology and properties of waterborne polyurethane (WPU) reinforced with synthetic polymer of polyvinyl alcohol (PVA) modified GO/zinc oxide (GO/ZnO) and functionalized carbon black/ZnO (CB/ZnO) nanocomposites. The incorporation of nanofillers into PVA matrix offers the opportunity to develop nanocomposites with enhanced anchoring effect and barrier protection properties. For the first time, we have compared CB and GO nanocomposites for its corrosion protection, latter was found to be superior in resistance to corrosion than former. The prepared nanocomposites were characterized by XRD, FESEM, XPS, Raman spectroscopy and contact angle measurements. The corrosion resistant properties were investigated by potentio-dynamic polarization studies using Tafel parameters and electrochemical impedance spectroscopy. Incorporation of 0.1–0.3 wt% of nanofillers in WPU dispersion has produced effective nanocomposite, with a resistance to corrosion on mild steel. This observation is in good qualitative agreement with the surface wettability and dispersion level of the nanocomposite in waterborne medium. This study has showed a new approach for synthetic polymer PVA anchored GO/ZnO and CB/ZnO which acts as filler in waterborne medium enhances the anti-settling behavior and resistance to corrosion. Moreover, by comparing these results reveal that, PVA anchored GO supported nano ZnO is higher in performance than PVA anchored CB supported nano ZnO in WPU dispersion.