الفهرس 
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Abstract
Summary and conclusions
‘’Studies on the synthesis and characterization of some eco-friendly corrosion inhibitive pigments for coating applications”
A-Summary:-
The aim of this thesis is to provide a detailed overview of an paint system (pigment/ environmentally acceptable anti-corrosion) based on epoxy, alkyds, resin with environmentally friend phosphomolybdate pigments synthesized form elements (Magnesium - Manganese - Zirconium - Vanadium) with Cobalt Ferrite oxide and Manganese ferrite oxide in the nano-meter size and Cerium oxide @titanium oxide Cobalt Ferrite @silicon oxide in nano-meter size as a new type of anti- corrosion inhibiting coatings with long-term high performance to protect more metallic surfaces from corrosion and rust.
This thesis includes four main chapters, introduction ,experimental ,result and discussion the two summaries in Arabic and English and the indexes.
Chapter One Introduction:
This chapter presents a scientific background on corrosion, and the properties of some phosphate pigments, molybdates, their advanced metallic admixtures, phosphomolybdates (POMs, POMs-and phosphomolybdate). It includes references for the previous ten years and their uses with a survey of Arabic summary
Chapter two Experimental Part:
This Chapter includes the used chemicals, their various sources, and some of their properties. It also describes methods for preparing these developed nanoparticles that are safe in the environment, and methods for preparing these developed pigments. Phosphomolybdate compounds (POMs), nano-cobalt ferrite, nano- manganese ferrite,nano-Ce2O@TiO2,nano cobalt ferrite @Silicon oxide and their derivatives phosphomolybdate.
It is also includes the most important techniques, methods and devices used
to identify and characterize it, such as FT-IR , X-ray spectral analysis ,morphology using a microscope AFM ,TEM& SEM ( atomic force ,scanning and transmission microscopy) to characterize phosphomolybdate compounds pigments also explained with alkyd resin and epoxy resin of various coating formulations approved by the IPOC, and explained how electrochemical tests and methods used in this field for use in international standards. Pigments and their various applications as corrosion inhibitors and protection of iron and metal surfaces.
Chapter three Result and discussion.
This chapter contains the result obtained in this work divided into two main parts as follow:
The first part
This part discussed the results of Corrosion tests of SEM & TEM and AFM of pigmented and powder of all composites, on the powder of metallic phosphomolybdate pigments developed with cobalt ferrite @ silicon oxide and metallic phosphomolybdate developed with cerium oxide @ titanium oxide. Its surfaces crystals have a morphological and the grain shape, as shown by the size, through the nano-meter range images, as it showed its dimensions.
Different coating compositions based on specific doses of them in combinations of coatings based on epoxy resin, where the results of different spectral measurements in infrared and X-ray diffraction were confirmed, in addition to the results of the chemical composition by scanning and transmission electron microscopy. It also showed the morphology of the crystals and the granular size of their surfaces, as it showed dimensions in the nano-meter range, through images and shapes recorded and built within the body of the thesis. In this study, composite coatings based on metal phosphomolybdate M-POM were synthesized to reinforce and protect stainless steel sheets. CeO2@TiO2/POM and CoFe2O4@SiO2/POM were synthesized and confirmed by spectroscopic measurements for example, X-ray diffraction (XRD) and atomic force microscopy (AFM) as well as TEM & SEM transmission and scanning electron microscopes. Corrosion tests of powder pigments for all composites, and epoxy-based coating films of CoFe2O4@SiO2/POM were investigated by Tafel dynamic polarization curve, and EIS electrochemical impedance spectroscopy to evaluate the corrosion resistance efficiency of the composites. The developed metal phosphomolybdates modified with cerium oxide and loaded with titanium oxide, tested in powder form, have good corrosion protection properties for 316 metallic surfaces.
Zirconium >-Vanadium >- Bismuth- POMs /CeO2@ TiO2 Core-Shell and for paint films: zirconium>-Vanadium >- Bismuth- POMs/ CoFe2O4 @ SiO2 .
As well as through the salt spray device for the painted steel films, the evaluation of the paint films for the vehicles and the observation and examination with the naked eye of the films that were examined electrochemically for the studies. They were examined by a gram, which contains a synthetic sea solution with a concentration of 35 grams of sodium chloride in a litter of water. The films were followed up and exposed to saline spray for an hour and the evaluation results were followed up and photographed every 250 hours and for 500 hours as follows:.
Zirconium >-Vanadium >- Bismuth- CoFe2O4 @ SiO2 / POM
The second part:
This part discussed the results of some nanoparticles of phosphomolybdate (magnesium - manganese - zirconium - Vanadium) which were synthesized with cobalt ferrite and manganese ferrite and evaluated as green an effective and anti-corrosion coating for commercial stainless steel Rust.
The synthesized compounds investigated using scanning and Transimition microscopy (SEM and TEM), AFM, FT- IR, XRD, EDX contact angle measurements. The results spectroscopy confirmed techniques, the incorporation both M- POMs and ferrite nanoparticles (NPs) into the composite matrices. Also the salt spray test In the medium of sodium chloride, its concentration is 35 grams per litter of water applied to confirm that M-POMs/Ferrite nano-particles have an effective and anti-corrosion coating for stainless steel.
M-POM contains new ferrite/alkyd resins and nanoparticles applied to substrates of commercial stainless steel sheets. Electrochemical techniques such as (Nyquist) EIS, Bode and Tafel were used to verify the anti-corrosion properties of the prepared coating techniques materials. And scanning the use microscopy of measurements revealed that Ferrite / M-POM composite coatings on commercial stainless steel sheets (SS). The polarization resistance of Nano-size pigment (M-POM) /ferrite compared to separated cobalt ferrite or M-POM has been increased as zirconium Oxide-POM / cobalt ferrite coatings from 1395 kΩcm2 to 6670 kΩcm2 for Manganese-POM /cobalt ferrite from 112.8 kΩcm2 to 692 kΩcm2 compared to other ferrite phosphomolybdate/cobalt compounds. As obtained from the Tafel measurements, the electrochemical measurements agreed with the results of the salt spray device. This indicates a high corrosion protection for the coated with Nano-size composite SS panels corrosion resistance compared showed to those phosphomolybdate alone.
B-Conclusions:-
Conclusion of first part:-
This study showed that after three weeks immersion of the coated steel panels in 3.5% NaCl solution for the corrosion test, eco-friendly (ZrO, Mn, VO, and Bi) -POMs/CoFe2O4@SiO2 nanocomposite coatings for stainless steel plates indicated enhanced electrical corrosion resistance performance. The electrochemical corrosion characteristics of the paint composites were greatly improved by the addition of CoFe2O4@SiO2 nanoparticles. High anticorrosion performance of the composite coatings was confirmed by EIS evaluations. from the electrochemical studies, the results showed that:
1-The Rct dramatically increased and the Cdl strongly decreased due to the adsorption of the metal-phosphomolybdate/ CoFe2O4 @ SiO2 on the surface of stainless steel.
2- The Tafel results are in agreement with the impedance results. The study confirmed the strong anticorrosion efficiency of the Zr=O, V=O POMs/cobalt ferrite@SiO2 nano composites for the protection of mild stainless-steel substrates.
3-In conclusion, the protection mechanism for POM/CoFe2O4@SiO2 nanocomposite coatings was governed by adsorption, and barrier effect due to the changes resulting from the formation of a more adhesion, denser and uniform layer on the steel surface. Initially, corrosive ions penetrate the coating and reach the surface of the steel, leading to anodic dissolution of the metal and a decrease in potential. Then, the nano-CoFe2O4@SiO2 form a passive protective layer at the steel surface which inhibits the corrosion, and enhances the corrosion-protection efficiency of POM/CoFe2O4@SiO2 nanocomposite coatings, as confirmed by EIS and potentiometric polarization study.
Conclusion of second part:-
This study revealed that the eco-friendly (ZrO, Mn, VO and Mg) POM / Ferrite nanocomposite coatings for stainless steel plates exhibited enhanced electrochemical corrosion resistance performance after corrosion test investigation by immersion in 3.5% NaCl solution for three weeks. The inclusion of cobalt ferrite nanoparticles in the composite significantly enhanced the electrochemical corrosion properties. EIS measurements proved a high anticorrosion performance of the composite coatings.
1-The Rct dramatically increased and the Cdl strongly decrease due to the adsorption of the metal-phosphomolybdate/ CoFe2O4 on the surface of stainless steel.
2-The Tafel results agreed and confirmed the impedance results. The study confirmed the strong anticorrosion efficiency of the zirconium, vanadium and manganese, POMs / cobalt ferrite nano composites for the protection of mild stainless-steel substrates.
3-SEM , Cross section images, physical and mechanical properties of MPOM / CoFe2O4 paint formulations results also agreed with the electrochemical studies
4- In conclusion, the protection mechanism for POM/CoFe2O4 nanocomposite coatings was governed by adsorption, barrier and locking effects of nano-ferrite, which inhibits the corrosion, and enhances the corrosion-protection efficiency of POM/CoFe2O4 nanocomposite coatings, which is also evident from wettability, EIS, potentiometric polarization study and the salt corrosion test.