Preparation of epoxy-organobentonite nanocomposites added ZnO-ZrO_2 /Al_2O_3-ZrO_2 nanoparticles and investigation on their corrosion resistance property in coating on Q235 steel

摘要

For purpose of synthesis new epoxy coatings to protect the structural steel in sea environment, in this paper, two epoxy-based nanocomposite samples containing low-loading of ZnO-ZrO_2/ZrO_2-Al_2O_3 nanoparticles and organobentonite nanoparticles were prepared. Pure epoxy sample and epoxy-based composite added organobentonite nanoparticles were also prepared for comparison. Dispersion of metal oxide particles and organobentonite nanoparticles into epoxy-composites were evaluated by using XRD analyses. Microhardness, adhesion and corrosion resistance over 91 days of immersion in artificial seawater (ASW) solution of new composites were studied by Vickers' hardness test (HV test), cross-cut test, electrochemical impedance spectroscopy (EIS) and polarization curves, respectively. Results showed that combined use of low-loading fillers had a positive effect on the organobentonite exfoliation behavior in resulting epoxy-based nanocomposites. Hardness, adhesion of two novel composites increased in comparison to pure epoxy even though with epoxy-based composite added organobentonite only. Results also showed that nanoparticle fillers could significantly improve the corrosion resistance of the coated steel, with ZnO-ZrO_2-organobentonite fillers being the best.