Enhanced Dispersion of Graphene in Epoxy-Acrylic Waterborne Anticorrosion Coating: Bifunctional Ligands Linking Graphene to SiO₂

摘要

The dispersion of graphene was improved by using a bifunctional ligand p-aminobenzoic acid (PABC)to anchor graphene (Gr) to SiO2 particles (marked as SiO2-PABC-Gr). This can avoid the phaseseparation and improve the dispersion of graphene in coatings. The materials were characterized byFourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), X-raydiffraction (XRD) and Raman spectra to prove the linking structure. An epoxy-acrylic (EA) resin wasused as the binder, which contained COOH groups to connect with SiO2 particles. The synthesizedSiO2-PABC-Gr (1 wt%) was dispersed in EA resin and used as anticorrosion protection compositecoating of low carbon steel, and the corrosion resistance was investigated by potentiodynamicpolarization curve and electrochemical impedance spectroscopy (EIS). The results indicated thatgraphene was successfully linked to SiO2 by PABC, and the application in EA resin can significantlyimprove the anticorrosion ability of the coating, which can be attributed to the high dispersion ofgraphene.