Poly(vinyl alcohol–proline) as corrosion inhibitor for mild steel in 1M hydrochloric acid

Corrosion inhibitive behavior of newly synthesized water soluble semiconducting polymer composite poly(vinyl alcohol–proline) (PVAP) is focused in this article. The polymer was characterized by FTIR, SEM-EDX, and XRD techniques. Thermogravimetry and differential thermal analysis proved the thermal stability of PVAP. Gravimetry and electrochemical techniques were employed to study the corrosion inhibition performance of PVAP on mild steel in molar hydrochloric acid. 0.6 % (wt.) of PVAP provides a maximum inhibition efficiency of 94 % at 303 K. The role of concentration of PVAP, exposure time and solution temperature on the mild steel corrosion has been investigated. The polarization results showed that PVAP acts as mixed-type inhibitor and could serve as an effective corrosion inhibitor for mild steel in acid medium. Surface morphology of the mild steel specimen by FTIR spectroscopy proved the formation of polymer film.