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The purpose of this paper is to present the preparation of core-shell ferrites/kaolin pigments and comparing their efficiency in protecting metal substrates to original ferrites which were also prepared. Core-shell structured particles are recently gaining lots of importance due to their exciting applications in different fields; these particles are constructed from cores and shells of different chemical compositions which show ultimately distinctive properties of varied materials different from their counterparts. The new core-shell pigment is based on shell of different ferrites that comprises only 10-20 per cent of the whole pigment on kaolin (cores) which is a cheap and abundant ore that comprises 80-90 per cent of the prepared pigment. The new pigments do not only comprise two different components, but they also contain pigment and extender in the same compound; their loadings in the paint formulations ranges from 50 and 75 per cent of the whole pigment. The work showed that these eco-friendly and cheap core-shell pigments are comparable in their efficiency to that of ferrites in protecting steel substrates.

The different ferrites and ferrites/kaolin pigments were characterized using different analytical and spectrophotometric techniques, such as X-ray fluorescence, X-ray diffraction (XRD), scanning electron microscopy/energy-dispersive X-ray (SEM/EDAX) and transmission electron microscopy (TEM). Evaluation of these pigments was done using international standard testing methods (ASTM). After evaluation, the pigments were incorporated in solvent-based paint formulations based on medium oil-modified soya-bean dehydrated castor oil alkyd resin. The physico-mechanical properties of dry films and their corrosion properties using accelerated laboratory test in 3.5 per cent NaCl for 28 days were determined.

The results of this work revealed that ferrite/kaolin core-shell pigments were close in their performance to that of the ferrite pigments in protection of steel, and at the same time, they verified good physico-mechanical properties.

Treated kaolin can be applied in many industries beside pigment manufacture and paint formulations; it can be applied as reinforcing filler in rubber, plastics and ceramic composites. Also, it is applied in paper filling, paper coatings and electrical insulation.

Ferrite and ferrite/kaolin are environmentally friendly and can replace other hazardous pigments (e.g. chromates) with almost the same quality in their performance; also, they can be used in industries other than paints, for example paper, rubber and plastics composites.

The influence of thermal treatment conditions on titanium dioxide ceramics phase transformation, microstructure, physico-mechanical and electrical properties was studied. TiO₂ ceramic was prepared using extrusion technology and thermal treatment in air and subsequent annealing under high vacuum conditions. It has been observed that intense TiO₂ ceramic mass sintering occurs over the temperature ranging from 950 °C to 1100 °C. It is accompanied by crystallographic modification change from anatase to rutile. Ceramic sample annealing in vacuum causes formation of nonstoichiometric titanium oxide ceramics and as a result electrical conductivity of the material significantly increases. Using extrusion process relatively dense and mechanically resistant ceramic material can be obtained that can be used in different technological processes.

The paper aims to evaluate the anti‐corrosion performance of inorganic pigments included in paint systems based on plasticized‐chlorinated rubber for carbon steel in different environmental conditions.

Paint systems based on chlorinated rubber and inorganic pigments such as zinc chromate, zinc phosphate, red iron oxide and treated iron industry waste powder were prepared. Immersion in 3.5 percent salt solution, as well as outdoor exposure tests, were performed and the paint physico‐mechanical properties were tested to evaluate the paints' anti corrosive performance.

The concentration and the type of pigments included in the prepared paint systems control their anticorrosive performance.

The paper demonstrates how pigment consisting of treated iron industry waste powder could be used in anticorrosion paints for carbon steel.

The purpose of this paper is to report the use of zinc phosphate pigment as a chromate substitute for coatings on non‐ferrous metals (galvanized steel, pure aluminum, α‐brass and pure copper).

Paint systems based on zinc chromate and zinc phosphate pigments were prepared. The paints were tested for their physico‐mechanical properties. Testing of the anticorrosive properties of the zinc phosphate pigment in comparison with zinc chromate pigment was carried out by accelerated corrosion exposure, i.e. immersion in 3.5 percent salt solution and exposure for one year at five outdoor stations.

The possibility of replacing chromate pigment was assessed and the “gap“ observable between the performance of zinc chromate and zinc phosphate pigments was noted.

The non‐toxic inhibitive pigment, zinc phosphate, incorporated into a plasticized‐chlorinated rubber binder, could be applied successfully for the protection of non‐ferrous substrates.

Owing to the ongoing demand for the elimination of chromate‐ and lead‐based pigments and the need to identify effective replacements, phosphate and molybdate are finding increasing application in coating industry. In the study reported here, phosphomolybdates, the newest of the second generation of molybdate and phosphate pigments had been prepared, characterised and evaluated as anti‐corrosive pigments for coating applications.

In this study, Ca, Zn and Ca‐Zn phospomolybdates were prepared and characterised by chemical analysis and spectrophotometric measurements, X‐ray diffraction (XRD) and scanning electron microscopy (SEM), in addition to thermal gravimetric analysis (TGA). The pigments were also evaluated according to international standard testing methods. The conditions for the preparation of the phosphomolybdate pigments were established. Their anticorrosive properties were evaluated by incorporation in anticorrosive paint formulations using medium oil alkyd resin as a binder. The paint films were tested in artificial seawater for 28 days.

The results showed superior anticorrosive protection properties of the pigments prepared over their phosphate and molybdate counterparts, in addition to the high tinting strength of their golden yellow colours.

The method for enhanced production of the eco‐friendly phosphomolybdate pigments was novel and economically feasible.

Phosphomolybdates, the newest of the second generation of molybdate pigments incorporate a synergistic combination of phosphate and molybdate compounds and are believed to have exceptional corrosion inhibiting activity, which has allowed for more optimised applications in specific types of coatings. They are considered the best known and most frequently utilised non‐toxic eco‐friendly inhibitive pigments.

Kaolin (hydrated aluminum silicate) is one of few minerals that are found in nature in a relatively pure state which is abundant in many places of the world. In this research, a simple chemical treatment using traces of ammonium molybdate was carried out to enhance the anticorrosive properties of kaolin.

The steps of treatment of kaolin at 1,000°C were estimated. Characterization of three different combinations of aluminum oxide with iron oxide were studied using spectroscopic methods of analysis via X‐ray diffraction (XRD), transmission and scanning electron microscopy (TEM and SEM). Also, evaluation of the prepared pigments using (oil absorption, specific gravity, water‐soluble matter, and pH) international standard testing methods were estimated. Then these prepared pigments were incorporated in anticorrosive paint formulations based on medium oil alkyd resin as a binder, the physico‐mechanical and anticorrosive properties of paint films were detected by testing them in 3.5 percent NaCl solution for 28 days.

Introduction of small amounts of ammonium molybdate in kaolin promoted its physico‐mechanical and anticorrosive properties. Although, this process of treatment is economically feasible, treated kaolin can replace expensive commercial pigments found in markets with an almost near quality to their performance.

Treated kaolin can be applied in many industries beside pigment manufacture, and paint formulations, it can be applied as reinforcing filler in rubber, plastics, and ceramic composites. Also it is applied in paper filling, paper coatings, and electrical insulation.

Presents findings from a study of the effects of treating unbleached bagasse paper sheets with different resin solutions. Unbleached kraft bagasse paper sheets were treated with different resin solutions such as nitrocellulose, melamine formaldehyde, silicone, short and medium alkyd resin and the physico‐mechanical properties of the modified paper sheets were tested. The strength properties of treated paper sheets were highly improved especially in the case of treatment with melamine formaldehyde and silicone resin solutions. The effect of dipping time of paper sheets in different concentrations of resin solution on the strength properties was also investigated. Physico‐mechanical properties of thermally treated modified paper sheets with resins were also clarified. Concludes that promising results in the improvement of insulation of treated paper sheets with resin are obtained by studying the dielectric‐electric properties.

To evaluate the performance of the compatibiliser of epoxidised soyabean oil‐free fatty acid prepared on the NBR/EPDM blends compared with maleic anhydride and also to explore the effect of loading the compatibiliser NBR/EPDM rubber blend with unmodified and modified polypropylene fibres on the mechanical properties of the blend.

To achieve desirable rheological and physico‐mechanical properties of NBR/EPDM rubber blend, various compositions were made by incorporating different doses of the compatibiliser of epoxidised soyabean oil‐free fatty acid prepared and maleic anhydride to form NBR/EPDM blends. The effect of loading the compatibiliser rubber blend with unmodified and modified polypropylene fibres on the mechanical properties of the blend was investigated.

The incorporation of epoxidised soyabean oil‐free fatty acid or maleic anhydride into NBR/EPDM blend greatly enhanced their compatibility improved the rheological, as well as physical properties of rubber blends. The addition of NBR to EPDM improved the motor oil swelling resistance of EPDM. Blending of the two individual rubbers without a compatibiliser generally exhibited a non‐synergistic effect with respect to the physical properties. The strain energy, tensile strength, Young's modulus and strain at yield varied linearly with composition in the presence of compatibiliser, but deviated from linearity in the absence of compatibiliser. Reinforcement of the NBR/EPDM blend with modified polypropylene fibres enhanced the physical properties more significantly than with the unmodified ones.

The compatibiliser of epoxidised soyabean oil was prepared by reacting in situ soyabean oil‐free fatty acid with per‐acetic acid.

The method developed provided a simple and practical solution to improving the rheological and physico‐mechanical properties of the NBR/EPDM rubber blend.

The method for enhancing rheological and physico‐mechanical properties of NBR/EPDM rubber blend loaded with modified polypropylene fibres was very important and showed a synergistic effect and could find numerous applications in the rubber and plastic industries.

The purpose of this study is to develop poly(etherfattyamide) coatings from Pongamia glabra seeds oil utilizing a sustainable resource, which is non edible, non medicinal and goes as waste. Seed oil based poly(etherfattyamide) is used as a coating material to improve the coating properties especially gloss and alkali resistance.

Pongamia glabra oil was first converted into N,N′ bis 2‐hydroxyethyl Pongamia glabra oil fatty amide (HEPFA). HEPFA was treated with 1,4‐cyclohexanedimethanol (CHDM) to develop poly(etherfattyamide) (PEFA). PEFA was cured with (butylated melamine formaldehyde) (BMF) in different (35, 40, 45, 50) phr (part per hundred part of resin) to produce coating material. The structural elucidations of HEPFA and PEFA were carried out by FT‐IR, ¹H‐NMR and ¹³C‐NMR spectral techniques. The thermal study was performed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. The physico‐mechanical and chemical resistance/anticorrosive properties were investigated by standard laboratory methods.

The authors developed a good coatings material from a sustainable resource. The physico‐mechanical and anticorrosive performance evaluation exhibits satisfactory results. PEFA‐BMF coatings material showed good alkali resistance and high gloss. The thermal studies showed that PEFA‐BMF45 may be safely used up to 225°C.

BMF modified PEFA coatings showed the highest scratch hardness 3.5 kg, flexibility (1/8 inch conical mandrel bend test) and gloss at 45° is 76‐82. Among all, PEFA‐BMF45 showed the best physico‐mechanical and chemical resistance performance. Thus, it may be used as an efficient coating material.

The synthesis of BMF modified PEFA from Pongamia glabra oil using 1,4‐cyclohexanedimethanol has been studied for the first time providing a new approach to utilize a non edible seed oil – a sustainable resource.

The purpose of this work is to prepare new core-shell pigments based on silca fume waste as core and ferrite pigments in the shell. Silica fume is a byproduct of the smelting process in the ferrosilicon industry. The reduction of high-purity quartz to silicon at temperatures up to 2,000°C produces SiO₂ vapours which then oxidize and condense at low-temperature zones to tonnage amounts of tiny particles consisting of non-crystalline silica that is collected and sold rather than being land-filled because nowadays there is increasing environmental concern with regard to excessive volumes of solid waste hazards accumulation. Silica has no direct effect in protecting metals from corrosion, but on precipitating an effective anticorrosive pigment like ferrite on its surface with low concentrations, this can bring out new core-shell pigment with good anticorrosive performance and low cost. The new pigments will be constructed on a waste silica fume core comprising 80-85 per cent of its chemical structure and the ferrite shell that will be only about 20-15 per cent. These pigments are represented as efficient, economically feasible and eco-friendly.

The different ferrites and ferrites/SiO₂ pigments were characterized using different analytical and spectro-photometric techniques, such as X-ray diffraction, scanning electron microscopy/energy-dispersive X-ray and transmission electron microscopy (TEM). Evaluation of these pigments was done using international standard testing methods american standard testing methods (ASTM). After evaluation, the pigments were incorporated in solvent-based paint formulations based on medium oil-modified soya-bean-dehydrated castor oil alkyd resin. The physico-mechanical properties of dry films and their corrosion properties using accelerated laboratory test in 3.5 per cent sodium chloride for 28 days were determined.

The results of this work revealed that ferrite/SiO₂ core-shell pigments were close in their performance to that of the ferrite pigments in protection of steel, and at the same time, they verified good physico-mechanical properties.

As silica fume has a large array of uses, these pigments can be applied in various industries such as painting, wooding coating, anti-corruption coating, powder coating, architectural paint and waterproof paints.

Ferrite, ferrite/SiO₂ are environmentally friendly pigments which can impart high anticorrosive behaviour to paint films with concomitant cost savings.