Anticorrosion properties of epoxy/nanocellulose nanocomposite coating

Abstract

Nanocellulose (NC) is an attractive reinforcement agent that can be incorporated into protective coatings because it is a renewable, biodegradable, and biocompatible polymer resource. In this study, a series of epoxy resin-based nanocomposites were prepared in the form of coatings with various amounts of NC loadings, and the coatings were applied onto mild steel at room temperature. The characterizations of the NC and nanocomposites were performed via X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and Fourier transform infrared spectroscopy (FTIR). The thermophysical properties of the nanocomposites were evaluated using differential scanning calorimetry (DSC) and thermogravimetry (TGA) analyses. The transparency of the nanocomposite specimens was examined by ultraviolet visible (UV-Vis) spectroscopy in the range of 300 to 800 nm. The corrosion protection properties of the coated mild steel substrates immersed in a 3.5% NaCl solution were studied comparatively by electrochemical impedance spectroscopy (EIS). The results showed that all of the nanocomposite coatings with NC noticeably influenced the epoxy-diamine liquid pre-polymer, both physically and chemically. Furthermore, the 1 wt.% NC nanocomposite coating system was found to have the most pronounced anti-corrosion properties, as confirmed by a 30-day EIS study.