Industrial polypyrrole electrodeposition on zinc-electroplated steel

Polypyrrole films were electrodeposited on zincated surfaces in a one-step process from aqueous solutions of sodium salicylate and pyrrole. This electrolyte passivates the substrate and makes it possible to obtain strongly adherent PPy films with controlled thickness by electrolysis at constant current. With a view to industrial application for rapid polymerization on common metals, an aqueous solution of 2 M sodium salicylate and 0.5 M pyrrole at pH 5 and room temperature provides optimum conditions. Laboratory studies and deposition with a pilot cell show that 2 mum of polymer can be deposited in 1 s with a current density of 70 A dm(-2).