الفهرس 
CHAPTER I (INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
It is well known that steel and zinc are important materials in different industrial processes. The corrosion and corrosion inhibition of zinc and steel in different media become very interesting and important owing to their wide applicability in industry. The purpose of the present study, the polymer growth on steel in different acidic solutions to protect it from corrosion in 0.3M NaCl aqueous media by using polarization potentials measurements. The investigation also was to study the corrosion and corrosion inhibition of zinc in different concentrations of hydrochloric acid by different techniques such as gasometric, and thermometric techniques.
The work also aims to study the inhibition effect of some amino-acids and thiourea, as corrosion inhibitors towards the dissolution of zinc in 2M and 4M HCl by using gasometric and thermometric techniques respectively.
The thesis comprises there main chapters:-
Chapter I is an introduction, about the importants types of corrosion, the general properties of zinc, classification of steel, synthesis of conducting polymers, the ways of corrosion inhibition and to a review on the relevant literature related to the project of investigation.
Chapter II deals with experimental part, which include the materials, sample preparation and different techniques.
The measurements method classified into three different types,
1- Gasometric technique.
2- Thermometric technique.
3- Polarization measurements technique.
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Chapter III is devoted to the (results and discussion) and consists of three parts:
Part A, is concerned with the corrosion behavior of zinc in different concentrations of HCl and in 2M HCl in absence and presence different concentrations of different inhibitors by gasometric technique.
Part B, offers the effect of some amino-acids and thiourea on the corrosion of zinc in 4M HCl by using thermometric technique.
Part C, displays the effect of different polymers with different thickness in different solvent preparation on the corrosion protection of steel in 0.3M NaCl aqueous solution by using polarization measurements technique.
The obtained results can be drawn from this work are,
1- Before the active dissolution process there is an incubation period in gasometric and thermometric technique, which is found to depend on the acid concentration.
2- The incubation time decreases with increasing the acid concentration.
3- The data reveal that the amino-acids additives retard the gas evolution reaction as well as the dissolution process.
4- The gasometric technique is not good to calculate the corrosion reaction rate of zinc in HCl solutions in presence of thiourea inhibitor.
5- The results show that lysine is superior inhibitor than the another used inhibitors on zinc surface in HCl solution.
6- Thermometric technique shows that the inhibition efficiency of the used inhibitors in the reaction of zinc with 4M HCl solution,
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increases according to the order: Thiourea > Glycine > Valine >
Tyrosine > Proline > Lysine.
7- The corrosion rate of zinc is inversely proportional with the logarithmic concentration of the used additives.
8- The adsorption of the tested inhibitors on zinc surface obeyed Langmuir’s adsorption isotherm.
9- The corrosion resistance of polymer coatings steel was higher than of uncoating steel.
10- There is a good correlation between the porosity (P) values of polymer coating steel and the degree of corrosivities. High porosity shows high corrosion current, however low porosity tend to retard corrosive action of chloride ions.
11- The corrosion parameters, ίcorr., I.E.%, and P of polymers coating steel depend on thickness of polymer coating, solvent of polymer preparation, and polymer type.
12- The inhibition efficiency of poly-N,N-dimethylaniline coating steel is superior than polyaniline coatings steel at the same conditions.