Abstract :
This study is concerned with the synthesis and characterization of new Conductive polymer films (3830 µs/cm) poly 6-((1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)carbamoyl) cyclohex-3-ene-1-carboxylic acid (PDPC) on the surface of low carbon steel electrode (L.C.S), which were synthesized starting from 6-((1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)carbamoyl) cyclohex-3-ene-1-carboxylic acid (DPC) as a monomer by electropolymerization method. Also, the ability of this polymeric coating to protect the surface from corrosion was tested in a saline solution 3.5% NaCl at various temperatures ranging from (298 to 328)K using a potentiostat that measures the corrosion rate by plotting Tafel lines. The new polymer-nanocomposites were also synthesized by adding nanometal-oxides: Zirconium dioxide (ZrO2) or Magnesium oxide (MgO) to the monomer solution to improve the anticorrosion properties of the prepared polymeric films. The functional groups, phase composition, and morphology of the prepared coatings were investigated using a Fourier Transform Infrared (FTIR) analysis, X-ray diffraction (XRD), and Atomic Force Microscopy (AFM). The examination of kinetic and thermodynamic activation parameters (Ea, A, ΔH*, and ΔS*) showing data results that the activation energies of L.C.S corrosion increased after coating due to the increasing energy barrier for the corrosion process and the best protection efficiency was 90.4 % at 298 K in case of using PDPC-ZrO2 nanocomposite as a coating.
Keywords :
corrosion , low carbon steel , Electrochemical polymerization Nanocomposite , Tafel