Reaction of poly(methyl methacrylate / maleic anhydride) with phenylhydazine and 4- aminobenzoic acid and their use as mild steel (ST-37) corrosion inhibitor

In this study, phenylhydrazine and 4-aminobenzoic acid were reacted with co-polymer (methyl methacrylate / maleic anhydride) and in the following, used as a corrosion inhibitor of low carbon steel. The chemical structure of copolymers was identified by spectroscopy of FT-IR and H-NMR, also titration and viscosity test. the amount of thermal resistance synthesized copolymers was investigated by thermal analysis of TGA, DTG and DSC. the results indicated that the thermal resistance of P (MMA-MA) / PhH and P (MMA-MA) / ABA in comparison with the (MMA-MA) has increased. In the following, via electrochemical potentiodynamic polarization tests, EDX and FE-SEM, the effectiveness and inhibition capability of copolymers in hydrochloric acid of 0.5 mol was investigated. The results showed that corrosion rate of co-polymers are (MMA-MA) <P(MMA-MA) /PhH <(P(MMA-MA)/ABA respectively.