Inhibition of biocorrosion of aluminum 2024 aeronautical alloy by conductive ladder polymer poly(o -phenylenediamine)

Abstract

The present study examines the role of conductive polymer poly(o-phenylenediamine) in corrosion inhibition and its antibacterial activity against bacterial biofilm (Bacillus cereus ACE4) on aluminum 2024 aeronautical alloy (AA 2024). Poly(o-phenylenediamine) (PoPD) was successfully electropolymerized by cyclic voltammetery on AA 2024 using sulfuric acid solution containing o-phenylenediamine monomer. The PoPD coating was characterized by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopyenergy-dispersive X-ray (SEMEDAX) spectroscopy analysis. The PoPD was polymerized on the metal surface as thin, transparent layers with a ladder conductive polymer structure. Results showed that the charge transfer resistance of the PoPD coating were higher (8.17 K and 3.28 K) when compared to a pristine and bacterial inoculated system (2.60 and 0.23 K). The PoPD coating effectively inhibits the adhesion of biofilm on AA 2024 due to its biocidal property, demonstrating that PoPD is a novel and superior candidate for the inhibition of biocorrosion by B. cereus ACE4 in an aeronautical fuel storage tank. © 2011 American Chemical Society.