Synthesis and Evaluation of Maleic Anhydride-Methyl Oleate Copolymer as a Corrosion Inhibitor for C-steel in 0.1 M HCl Solution

摘要

The present study investigated the synthesis of a copolymer of maleic anhydride and an ester of oleicacid. Poly (maleic anhydride-co-methyl oleate) was prepared via the free radical polymerization ofmaleic anhydride with methyl oleate. The prepared copolymer was Characterized via FTIR and GPCand thermal analyses (TGA and DTA). TGA demonstrated that the prepared copolymer was thermallystable up to 146 °C. Electrochemical measurement tests, including potentiodynamic polarization tests,revealed that the prepared copolymer was successfully applied as an organic corrosion inhibitor for Csteel in 0.1 M HCl solution at 298 K, 308 K, 318 K and 328 K. Potentiodynamic polarizationmeasurements revealed that this copolymer was a mixed-type corrosion inhibitor. Its inhibitionefficiency was measured on the basis of potentiodynamic polariaztion curves via the electrochemicaltechnique. Results demonstrated that the corrosion inhibition efficiency of poly(maleic anhydride-comethyl oleate) increased with concentration and decreased with increasing temperature. Inhibitionefficiency reached 94.8% with 20 ppm poly (maleic anhydride-co-methyl oleate) at 298 K. Theadsorption of this copolymer on the C-steel surface was chemical adsorption and obeyed the Langmuiradsorption isotherm.