Designing and fabricating of time-depend self-strengthening inhibitor film: Synergistic inhibition of sodium dodecyl sulfate and 4-mercaptopyridine for mild steel

12-Sodium alkyl sulfate (SDS) was used as supporting frame for the adsorption of 4-mercaptopyridine (4MP) molecules, and the synergistic effect of 4MP and SDS (MP-SDS) was studied. Long time immersion tests showed that MP-SDS inhibitor film changed from monolayer to bilayer structure with time. Owning to the occurrence of the inhibitor bilayer, the corrosion inhibition loss induced by the de-adsorption of first inhibitor layer after long period of immersion was recuperated. MP-SDS shows good synergistic inhibition performance toward the corrosion of the steel in 0.5 M HCl solution. The relative synergistic mechanism was finally discussed. (C) 2018 Elsevier B.V. All rights reserved.