Exploring the relationship between the surface chemistry and the corrosion behavior of electropolymerized polypyrrole films deposited on the surgical ISO 5832-1 stainless steel

In the present work, electropolymerized polypyrrole (PPy) films were obtained on the surface of the surgical ISO 5832-1 stainless steel. The films were obtained from solutions containing 0.1M and 0.5M of the monomer by cyclic voltammetry deposition. The correlation between the surface chemistry of the as-deposited films and the corrosion behavior of the coated substrate is explored. X-ray photoelectron spectroscopy was used to study the chemical state of the main elements in the PPy films. Electrochemical impedance spectroscopy and potentiodynamic polarization tests were employed to evaluate the corrosion resistance of the PPy-coated samples. The tests were conducted in phosphate-buffered saline solution at 37°C. The measured corrosion current densities were dependent on the doping level of the PPy film and decreased with the reduction of the doping level of the PPy layer.