Synthesis, characterization and anticorrosive properties of poly(aniline-co-o-toluidine-co-o-aminobenzoic acid)/ TiO2 nanocomposite

摘要

Terpolymer of aniline (AN), o-toluidine (OT) and o-aminobenzoic acid (OABA), poly(AN-OT-OABA) and its composite with TiO_2 nanoparticles, poly(AN-OT-OABA)/TiO_2 were prepared by chemical oxidative polymerization, via an emulsion method, using ammonium persulfate as an oxidant and HCl as an external dopant. The nanocomposites of homopolymers, polyaniline/TiO_2, poly(o-toluidine)/TiO_2 and poly(o-aminobenzoic acid)/TiO_2 were also synthesized by following similar synthesis route. The synthesized terpolymers/homopolymers were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The synthesized compounds were chemically deposited on loe carbon steel specimens by solution evaporation method using N-metyhl-2-pyrrolidone (NMP) as solvent and 10% epoxy resin as binder. Anticorrosive properties of homopolymers/terpolymersnanocomposite coatings were evaluated in 3.5% NaCl solution at a temperature of 30°C using open circuit potential (OCP) measurements, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization measurements (PDP) and SEM. The anticorrosive properties of terpolymernanocomposite were found superior to terpolymer and its homoplymers nanocomposites.