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Modern glues are manufactured with high moisture and water resistance; urea‐formaldehyde resins for gluing purposes are based on the fact that excellent control of the condensation reaction is possible by variation of pH, which can be applied easily at the production process. Among conclusions is that the shear stress of these resins is twice that of the unmodified type.

This paper is concerned with the study of silica fume that arises in tonnage amounts during the manufacture of ferrosilicon alloys; this was done in order to maximize productivity and to create new market for industrial by‐product and/or waste material.

The structure and particle shape of silica fume were identified using X‐ray diffraction and electron microscope, respectively. Standard methods were used for the identification of chemical analyses, solubility, hydrogen ion concentration, specific gravity, bulking value, oil absorption, chemical resistance and particle size. The characterized and evaluated silica fume was applied in several paint formulations. The physico‐mechanical, chemical and corrosion protective properties of the paint films were measured according to standard methods.

The silica fume under investigation was a fine lightweight fluffy amorphous powder. It has a grayish‐white color that makes it suitable for use as a filler and extender pigment in a wide variety of different fields of application; its amorphous nature favors safe use from a standpoint of industrial hygiene. It can be used as an economic pigment that possesses suitable values of specific gravity, bulking value and oil absorption. It also is inert, neutral and of an excellent chemical resistance. The material can be used successfully as an extender pigment in different paint formulations; taking into consideration that alkyd resin based paints should not be used in alkaline environments or mixed with basic pigments, or the paint film will deteriorate. Silica fume particles in the pigment mixture may offer a suitable opportunity for the voids formed by the larger particles to be occupied by smaller ones to produce a condition of maximum packing. It can be successfully used with the flaky aluminum or stainless steel anticorrosive pigments to produce a highly efficient corrosion protective film.

There is increasing environmental concern with regard to excessive volumes of solid waste hazards accumulation. Silica fume that arises – as a disposal material – in tonnage amounts during the manufacture of ferrosilicon alloys can find a new market in paint industry. It can be used successfully for anticorrosive paints to provide well backed paint films.

Zinc‐ferrite pigment was prepared by solid‐state reaction. A mixture of α‐Fe₂O₃ and ZnO in a molar ratio of 1:1 was fired at 1,200°C. X‐ray diffraction measurements proved that the reacted material crystallized into a spinal structure. Measurement of the pigment specification and properties were carried out according to standard international methods. The pigment extract and the extract of the pigment‐linseed oil mixture were examined for use in protecting steel panels against rust. The prepared pigment was incorporated in some paint formulations. Physical, chemical and mechanical properties of the formulated paint films were studied and also tested for corrosion resistance. Finds that zinc ferrite is a basic pigment and can be recommended for use in anti‐corrosive paints. High corrosion‐resistant coatings can be obtained by incorporating zinc‐ferrite pigment in organic coating systems that cannot saponify; protection increases as the pigment‐binder ratio increases. Chemically follows up and physically emphasizes the mechanism of corrosion protection by the use of a Mossbauer spectroscope.

The purpose of this paper is to study the corrosion protective properties of modified urea and/or thiourea formaldehyde resins for steel surface.

Three butyl alcohol modified amino resins were laboratory prepared. The three modified resins were characterized using thermal gravimetric analysis and infrared; the solid content and refractive index of each were also measured.

The resins that contain both nitrogen and sulphur have excellent corrosion inhibitive activity compared with that containing nitrogen only.

The modified resins were based on urea formaldehyde resin, mixed urea and thiourea formaldehyde resin and thiourea formaldehyde resin, respectively.

The prepared resins were introduced in different coating formulations based on short‐oil alkyd resin, medium‐oil alkyd resin and plasticized chlorinated rubber. They were then tested and evaluated for corrosion protection of steel surfaces.

All the prepared resins show promising results for corrosion protection of steel surfaces.

Twelve pigment compositions derived from the xCaO·(50−x)ZnO·20B₂O₃·30P₂O₅·(x=10, 20, 30) and yMgO·(50−y)ZnO·20B₂O₃·30P₂O₅·(y=10, 20, 30) systems were prepared. The synthesis was carried out either by the medium‐temperature process or by the high‐temperature process followed by cooling in air and an isothermal crystallisation of the glass obtained. The pigments prepared by the medium‐temperature process achieved better corrosion results in styrene‐acrylate coating formulations, whereas those prepared by the high‐temperature process achieved better results in alkyd‐resin coating formulations. The anti‐corrosion results for the Ca‐Zn pigments were better than those for the Mg‐Zn pigments.

Long time ago, multistructured materials showed great interest being considered as the bridge between bulk and atomic materials. Core-shell particles are kind of composite materials that refer to multilayered structures with a core totally surrounded by shell(s) (onion-like structure). These new structures can offer an advantage of applying new adjustable parameters like shape, stoichiometry and chemical ordering, in addition to the opportunity of tailoring more complexed structures for different applications. Recently it was found that these structures can be tuned and taken for more advanced path with novel structures formed of core surrounded by multishells. The purpose of this study is to study the effect of the new anticorrosive pigments with its mutual shells and how each shell affects the performance of the pigment in protecting the metal and which shell will be more relevant in its effect.

The prepared pigments were characterized using X-ray fluorescence, X-ray diffraction, TEM and SEM/EDX to prove their core-shell structure, and then they were integrated in coating formulations to evaluate their anticorrosive activity using immersion test and electrochemical impedance spectroscopy (EIS).

The results showed that the prepared core-shell pigments possess a lot of unique characteristics and can offer improved anticorrosive performance in the generated coatings.

Core-mutual shells structured pigments were prepared for improving the corrosion resistivity of the organic coatings as a new trend in anticorrosive pigments.

New types of phosphate pigments which are appropriate alternatives for hazardous chromate pigments have been prepared and evaluated. These new pigments were prepared via a new technique named core-shell. The core-shell materials consist of at least two separate phases with different chemical compositions. Recently, these materials have become more significant because they have the advantage of gathering the properties of both cores and shells that help to overcome the defects that they might possess individually. The purpose of this research is to develop a modified silica fume-phosphate core-shell pigment that contains 80-90 per cent of waste material (silica fume) and at the same time can offer promoted mechanical and anticorrosive properties than silica fume and they can also be compared with phosphates. The pigments have shells of Zn, Mn, Zn.Mn phosphates comprising about 10-20 per cent.

The prepared core-shell pigments have been characterized using several methods, which have then been integrated in alkyd paint formulations. The physical and mechanical properties of dry films and their corrosion prevention using accelerated laboratory test in 3.5 per cent NaCl for 28 days are estimated.

This study showed that the performance of these new pigments is highly efficient in corrosion protection, and it can be a suitable alternative to phosphate pigments despite containing phosphates which does not exceed 20 per cent of the composition.

Waste materials were reused in paints and only simple modification was used; their effectiveness was high and can be compared with well-known pigments.

Silica-phosphate core-shell pigments are environmentally friendly pigments that can replace other hazardous pigments (e.g. chromates and phosphates) with almost the same quality in their performance.

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.

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.

The purpose of this paper is to report the electrochemical verification of anticorrosive properties of NiZn ferrites as pigments in protective coatings and evaluation of their microwave absorbing properties.

Ferrites, represented by formula Ni_xZn_(1−x)Fe₂O₄, where x=0, 0.2, 0.4, 0.6, 0.8, 1.0, were synthesized using a ceramic method. The samples of ferrites were examined by X‐ray diffraction and SEM. Immersion tests in ferrite extracts, combined with electrochemical tests using techniques such as polarization curves, linear polarization and electrochemical impedance spectroscopy (EIS) were involved to determine the protective action provided by the ferrites. Epoxy coatings containing 10 vol.% of the ferrite were investigated using EIS. Experimental verification is provided of the microwave attenuation capability of coatings containing the investigated ferrites. Reflection loss, measured in the frequency range of 6.5‐15 GHz, exhibited maximum attenuation at a level of 8‐16 dB.

The results obtained suggest that NiZn ferrites possess active anticorrosive properties and support inhibition of the cathodic reaction by scale deposition at the metal substrate in an alkaline environment created by the pigments and the cathodic reaction. Additionally, they can serve as a microwave suppressor.

NiZn pigments can be used in coatings to serve simultaneously as an active anticorrosion, non‐toxic pigment and a material protecting against electromagnetic interference problems.

The paper provides information regarding the anticorrosive properties of NiZn ferrites as pigments for protective coatings and also microwave absorbing materials. An attempt was made to elucidate the potential mechanism of anticorrosive action of these pigments.