Corrosion performance of chemically polymerized poly(pyrrole-co-o-toluidine) coating on mild steel

Abstract

The Poly(pyrrole co o toluidine), (PY/OT) copolymer was prepared by chemically oxidative polymerization of pyrrole (Py) and o toluidine (OT) in HCl aqueous medium. The copolymer was charac terised by using Fourier Transform Infrared Spectroscopy (FTIR) technique. The coating of PY/OT copoly mer on 8 Hydroxyquinoline sulphonic acid (HQSA) pretreated mild steel surface was chemically deposited using N methyl 2 pyrrolidone (NMP) as the solvent. The corrosion performance of the PY/OT copolymer coating on steel, both scribed and unscribed samples, was studied by conducting immersion tests and electro chemical tests which include free corrosion potential measurements and potentiodynamic polarization mea surements. The above tests were conducted in different corrosive media which include 0.1 M HCl, 5% NaCl solution, artificial seawater and distilled water. The performance of coating in open atmosphere was also eval uated by conducting atmospheric exposure test. The results of different studies indicate that PY/OT copoly mer coating may be considered as potential coating material for corrosion protection of mild steel in the above corrosive medium.

Selective Fabrication of an Electrochemical Sensor for Pb2+ Based on Poly(pyrrole‐co‐o–toluidine)/CoFe2O4 Nanocomposites

“…From literature (–NH–) stretching vibrations of POT appears at 3372 cm –1 and (–NH–) vibration peak of PPy is hardly exhibiting. From (a) a broad and weak a band at 3465–3125 cm −1 , ascribed to the characteristic (–NH–) stretching vibration, suggests the appearance of (–NH–) groups in Py and OT . The aromatic and aliphatic C–H stretching vibrations appearance at 3022, 2967, 2923 and 2854 cm –1 respectively.…”

o-Toluidine in electrochemistry – an overview

“…Reasons for selection of o-toluidine were not provided, and based on impedance measurements, inhibition efficiencies > 90% somewhat depending on the comonomer ratio were observed. Such soluble copolymer was prepared by chemical polymerization; a coating on carbon steel was subsequently applied with a saturated solution of the dissolved copolymer in N-methyl-2-pyrrolidone 1 NMP [105]. Protection of up to 99.99% was reported; specific reasons for the use of o-toluidine were not provided.…”