الفهرس 
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Abstract
The present work includes three chapters chapter(l): Introduction: This chapter contains the .kinetics of the anodic oxidative electropolymerization of aniline, diphenylamine, N-methylaniline and their derivatives , characterization of the obtained polymer films by cyclic voltammctry , UV-visiblc , IR, ’H-NMR spectroscopy, X-ray diffraction studies , morphological investigations by SEM, thermal stability by TGA, factors affecting on the electropolymerization reactions, physical properties and structure of polymers which have been discussed in the literature. Chapter (2): Experimental:’ • Comprise the chemicals, experimental methods for the electropolymerization , cyclic voltammetry , corrosion protection, computer softwares. Techenique for the kinetic studies and calculations of the reaction order and activation thermodynamic parameters are given. characterization of the obtained polymer films by different instrumental technique such as UV-Visible, IR, ’H-NMR, elemental analysis, TGA, XRD and SEM is also given . Chapter(3): -Result and discussion: This chapter includes the layout of the obtained results and their discussions it contains four parts Part(l): In the first part , the kinetic of the anodic oxidative electropolymerization of aniline, diphenylamine and n-methylaniline in acid medium in presence of supporting electrolyte’ Na2S04 at different temperatures were investigated. The reaction rate law of the above electropolymerization systems are given by the following equation. Ri= k2 [current density]8 [monomer]b[HCI]c [Na2S04]d where a , b , c and d are the order of the electropolymerization reaction with respect to current density , Monomer , HC1 and electrolyte concentrations respectively. The reaction rate law in case of t” electropolymerization of aniline is as follow Ri= k2 (8]I13[0.07]U[0.8]U0 [0.09]0’58 In case of diphenylamine is Ri= k216|10 [0.091,l6[lll-,|0.07|0-48 Also, the apparent activation energy.(Ea), enthalpy (AH*) and entropy (AS*) were calculated for the electropolymerization reaction of aniline and diphenylamine but in case of N-methylaniline the apparent activation energy was calculated from cyclic voltammetric data. The data are given-in the following table. On AS* (Jic’mor’) AH* . (KJmoT1) Ea (KJmoT1) Name of monomer -115.42 87.69 90.22 Aniline -47.65 54.20 56.70 Diphenylamine II II 53.61 N-methylaniline The mechanisms of the anodic oxidative electropolymerization reaction of the investigated monomers in HC1 medium are also given. Part(2): This part includes the cyclic voltammetry measurements of the polymer formation in each case, the obtained results reveal the following: the I In case of aniline , it is clear that the voltammogram exhibit a couple of redox peaks, an anodic peak with peak potential at 180 and a cathodic peak with peak potential at 1078 m V In . case of N-methenylamine the voltammogram exhibit a couple of redox aks. an anodic peak with peak potential at 141 and a cathodic peak at 930 mV * in case of N-methylaniline the voltammogram exhibit a couple of redox peaks, an anodic peak with peak potential at 114 and a cathodic peak at 1318 mV part(3): In this part, the characterization of all obtained polymer films at the um conditions which gives homogenous and adhered film were estimated. The characterization tools are elemental analysis, absorption spectroscopy using IR, UV-Visible and1H-NMR instruments. X-ray diffraction analyses for the determination of polymer crystallinity are also investigated. This study assures that all .the investigated polymer films are crystalline structure except in case of n-methylaniline which is amorphous with small portion of crystallinity. This is also confirmed by scanning electron microscope investigation, which give an idea about the polymer morphology. Thermal analysis (TGA) is also investigated which confirm the suggested structures of the prepared polymers. Part(4): This part includes the application of the prepared polymer samples as corrosion protection for aluminum metal in acid medium. The corrosion behavior of polyaniline , polydiphenylamine and polyN-methylaniline in 1.0M HC1 was studied at different temperatures by using potentiodynamic anodic and cathodic techniques ..The results show that the adsorption of these polymers from aqueous solution to the surface of aluminum metal increase the corrosion resistance of aluminum. Since the presence of these polymer films decrease the values of the corrosion current density and enhance both the anodic and cathodic overpotentials. The corrosion protection efficiency of these polymers decrease in the following order polydiphenylamine |polydiphenyIamine> PolyN-methylanilne > polyaniline.