Corrosion is an electrochemical process that has constituted serious environmental problems to industries, homes and other environment. Metals of various types and grades are widely used in industrial installations and are often exposed to some aggressive media including acid, base and salt. Due to the fact that various industrial installations made of metals such mild steel, aluminum, and zinc are susceptible to corrosion attack during acid wash, etching, scale removal, etc., acid corrosion of these metals has garnered greater consideration and research. Numerous inhibitors have apparently been researched and used to reduce the rate of corrosion of important metals in light of these and other impacts, with positive results. The majority of the typical corrosion inhibitors, however, are poisonous, expensive, non-biodegradable, and difficult to get, according to environmental and other issues. The combination of inhibitors to improve anti-corrosive activity through synergistic actions remains a very important strategy for combating corrosion of mild steel. In this work, we combinedchitosan (CT) and polyvinyl propenenitrile (PVP), and explored their anti-corrosive action on mild steel in acidic medium via weight loss method. Results obtained from the weight loss experiment indicated that, the instantaneous inhibition efficiencies of the mixture of CT and PVP were higher than their individual inhibition efficiencies. Results showed that the corrosion inhibition efficiencies of a mixture of CT and PVP (77.49469 %) was higher than the individual components of CT (64.25 %) and PVP (52.02 %) at 303K.

Keywords : Chitosan, polyvinyl propenenitrile, corrosion, mild steel, synergism