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This study aims to perform the surface treatment of synthetic α-Fe₂O₃ red iron oxide pigment with hydrolysate 3-aminopropyl silane (A) and colloidal silica (CS) and investigate the effects of surface-treated pigment on the styrene acrylic (SA) emulsion and polyurethane (PU) dispersion.

For this purpose, firstly red iron oxide particles were modified with A and CS separately in an aqueous medium. After isolation of the modified iron oxide were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). Moreover, the degree of the dispersion stability of the modified pigment in coatings with SA emulsion and PU dispersion was investigated by using an oscillation rheometer. Loss (G''), storage (G') modulus, loss factor [tan(δ)] and yield stress (τ⁰) values were determined by performing amplitude and frequency sweep tests.

The τ⁰ in SA coatings decreases with the amount of used A and increases with the amount of used CS. The τ⁰ decreases as the amount of used A and CS in PU coatings increases. The use of CS on red iron oxide pigments causes storage modulus to increase in SA coatings at low angular frequencies, while it causes a decrease in PU coatings.

To the best of the authors’ knowledge, for the first time, the suspended state of the iron oxide hybrid pigment formed with CS in the coating was investigated rheologically in this study.

Several solid solution combinations of aluminium oxide and iron oxide, for the preparation of a new pigment, were investigated to study the effect of aluminium oxide to iron oxide ratio on various properties of the resulting pigments.

The conditions for the preparation of the pigments via solid solution interaction at 1,000°C had been estimated. Characterisation of three different combinations of aluminium oxide and iron oxide were carried out using spectroscopic methods of analysis via X‐ray diffraction (XRD), transmission and scanning electron microscopy (TEM and SEM). Also, evaluation of the pigments prepared, in terms of oil absorption, specific gravity, water‐soluble matter, and pH, using international standard testing methods was performed. The pigments prepared were incorporated in anticorrosive paint formulations based on medium oil alkyd resin as a binder. The physico‐mechanical properties of the relevant paint films were obtained, while their anticorrosive properties were assessed by tests in 3.5 per cent NaCl solution for 28 days.

The results showed that the anticorrosive protection properties of the pigment prepared were better than their aluminium and iron counterparts.

The pigments prepared may be used in different applications other than paint formulations. As the concentration of iron oxide increases, the hardness and the anticorrosive protection performance of the paint film increase. As the concentration of aluminium increases, elasticity, impact resistance and ductility also increase. Application of different combinations of these pigments in paint films had been studied. However, investigation of the application of these pigments in other systems such as plastics could also be interesting.

The pigments prepared can be used as reinforcing filler in different rubber and plastic composites, beside its ferro‐magnetic properties. As the concentration of alumina increased, the reinforcing and magnetic effects decreased and vice versa.

Iron oxide is an abundant ore in several world countries; it is an inorganic, environmentally friendly material, which exhibits good Moh's hardness. Adding aluminium oxide which is a very light element having a unique flaky structure to iron oxide gave a new pigment that can be used not only in paint formulations, but also in rubber and plastic composites as reinforcing fillers.

It is well known that iron oxide, a pigment widely used in the paint industry, can not bring about chemical inhibition of the corrosion process. This pigment, however, belongs to the semi‐conductor group and as such its structure is amenable to modification. The method essentially consists of mixing another oxide with iron oxide and subsequent calcination. The modified iron oxide was studied in four media viz., linseed oil, alkyd, chlorinated rubber and sodium silicate. The paints prepared in these media were evaluated by laboratory and natural weathering tests. The results have shown that the modified iron oxide pigment does bring about corrosion inhibition and that its performance is on a par with that of red lead in linseed oil and can be used with advantage. There is an overall saving in the cost of protection per unit area of iron and steel.

The purpose of this paper was to prepare and evaluate a nanosized mixed calcium iron oxide as a high heat-resistant pigment. Heat-resistant pigments can be defined as chemical substances that impart color to a substrate or binder and retain their color and finish at elevated temperatures. Mixed metal oxides have been widely used as pigments in coating formulations.

This work presents synthesis of nanosized calcium iron oxide as an inorganic pigment by using simple synthesis technique, namely, solid-state calcination method, to study its heat and corrosion resistance. The prepared pigment was characterized by using X-ray diffraction, infrared spectroscopy, scanning electron microscopy and inductive coupling plasma. It was incorporated into paint formulations, and the heat, corrosion and mechanical resistance of dry paint film was evaluated.

In this work, the prepared calcium iron oxide pigment showed excellent heat and corrosion resistance.

Heat-resistant coatings are required for industrial applications, mainly for reactors, exhaust pipes, space craft, stacks and similar equipments that are permanently and occasionally exposed to elevated temperatures. It was previously quite difficult to formulate heat-resistant organic coatings because of binder deficiencies; new vehicles for such applications are now available. Thus, the development of silicon resins has markedly advanced the utility of heat-resistant paints. High-temperature pigments are inorganic chemical compounds that impart and retain their color and finish to a substrate or binder at elevated temperatures.

The nanosized mixed calcium iron oxide could be used as a pigment in paint formulations. It was found that it significantly enhances the heat, corrosion and mechanical resistance. It can also find numerous applications in other paint formulations for surface coating.

The paper shows how the pigment consisting nanosized mixed calcium iron oxide could be used in heat-resistant paint formulations for coating metal surfaces.

To prepare of fine particle size magnesium ferrite pigments by sol‐gel method.

Different magnesium ferrite pigments with stoichiometric ratios were prepared by sol‐gel and dispersion methods. The characterisation of magnesium ferrite pigments were based on X‐ray diffraction, transmission electron microscope, particle size distribution, thermal and magnetometric analyses.

The type of polymer and the starting inorganic materials (oxides or salts) have a significant effect on the properties of the magnesium ferrite pigments prepared.

The magnesium ferrite pigments, prepared and used in the work reported here were synthesised from magnesium and iron oxides, oxalates and chlorides. Urea formaldehyde resin and acrylic polymer were used as the dispersing media. Various other materials, e.g. carboxymethyl cellulose, ethoxy methyl cellulose, polyvinylalcohol and 2‐hydroxyethyl methacrylate and polyacrylamide can also be used to achieve similar effect.

The sol‐gel method provided a fine particle size and different particle shapes. Therefore, the method of preparation could be used to produce fibres, films and monoliths.

The magnesium ferrite pigments prepared could be use in numerous paints for steel protection.

Because of rationalisation and demands for improved quality, the surface coatings industry makes ever‐increasing demands for micronised pigments. Micronised pigments permit quicker dispersion and increased output, coincident with decreased production costs. Such factors as the superior dispersibility of micronised pigments have frequently been mentioned, and it is not easy to quote new aspects of this. Therefore, this article will primarily cover other technical advantages of micronised iron oxide pigments‐advantages hitherto neglected in favour of the main advantage, better dispersibility.

The purpose of this paper is to investigate and explain thermal oxide effect on electrochemical corrosion resistance anodized stainless steel (SS).

Electrochemical corrosion resistance of thermal oxides produced on anodized 304 SS in air at 350°C, 550°C, 750°C and 950°C in 3.5 wt.% NaCl solution have been investigated by dynamic potential polarization, EIS and double-loop dynamic polarization. Anodized 304 SS were obtained by anodization at the constant density of 1.4 mA.cm^-2 in the solution containing 28.0 g.L^-1H₃PO₄, 20.0 g.L-1C₆H₈O₇, 200.0 g.L^-1H₂O₂ at 70°C for 50 min. SEM and EDS had been also used to characterize the thermal oxides and passive oxide.

Interestingly, anodized 304SS with thermal oxide produced at 350°C displayed more electrochemical corrosion and pitting resistance than anodized 304 SS only with passive oxide, as related to the formation of oxide film with higher chromium to iron ratio. Whereas, anodized 304SS with thermal oxide formed at 950°C shows the worse electrochemical corrosion and pitting resistance among those formed at the high temperatures due to thermal oxide with least compact.

When thermally oxidized in the range of 350°C–950°C, electrochemical corrosion and pitting corrosion resistance of anodized 304 SS decrease with the increase of temperature due to less compactness, more defects of thermal oxide.

Some organo‐metallic pigments namely copper phthalocyanine, metal and metal free biphthalocyanines, halogenated copper phthalocyanine and two inorganic pigments (red and yellow iron oxides) were incorporated into styrene butadiene rubber mixes (SBR). The rheometric characteristics and mechanical properties of the compounded rubber were investigated. The antioxidant efficiency of the above mentioned pigments were evaluated. Beside their good colouring effect the synthesized copper and nickel biphthalocyanines and the commercial red iron oxide have a significant effect on the properties of rubber vulcanizates after ageing. In addition, nickel biphthalocyanine and red iron oxide can be successfully used as ultraviolet stabilizers for rubber vulcanizates.

High strength low alloy steels have attained wide acceptance as structural materials. Research and development have led to different corrosion preventive methods. High strength low alloy (HSLA) of composition C(0.4%), Mn(0.7%), Si(0.25%). Cr(0.8%), Ni(1.7%) was selected for this study. Epoxy iron oxide, epoxy micaceous iron oxide (MIO), zinc‐rich epoxy and zinc ethyl silicate were used for painting the HSLA panels (150mm × 100mm × 3mm). Physical properties such as film thickness, specific gravity, viscosity, drying times of paints were evaluated and salt spray test, AC impedance and metallographic examination were carried out. Performance of zinc ethyl silicate coating over HSLA was found to be the best followed by epoxy micaceous iron oxide system.

The need for environmentally acceptable anti‐corrosive pigments to replace those based on lead and chromates in priming paints has stimulated the emergence of phosphate, molybdate and borate types and many others. However there are widespread doubts about the ability of these “non‐toxic” alternatives to provide the same degree of corrosion‐resistance as the lead and chrome pigments. This has encouraged a search for ways and means of boosting the inhibitive action of the newer pigments, for instance by mixing with other ingredients that might promote a synergistic effect. There has been a growing interest in utilising inert “barrier” pigments for this purpose and the development of synthetic iron oxide with a flake‐like crystalline structure is a significant step forward in this context.