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In recent years, zeolites have been highlighted as a new component in many industrial applications owing to their unique properties. The purpose of this study is to apply three prepared types of zeolites Na-X, Na-Y and hydroxysodalite (Na-HS) in anticorrosive paint formulations to be evaluated as a partial replacement to zinc phosphate in anticorrosive paint formulations to protect carbon steel.

The three types of zeolites were characterized using different instrumental analysis such as X-ray diffraction, scanning electron microscopy and X-ray fluorescence. Evaluation of zeolites was done using American society for material and testing. Then, they were incorporated in paint formulations based on medium oil-modified soya-bean dehydrated castor oil alkyd resin in the presence and absence of zinc phosphate. Their corrosion behavior was estimated using both immersion test and electrochemical impedance measurements in 3.5% NaCl.

Generally, the prepared zeolites exhibited good corrosion protection performance, but in presence of zinc phosphate the performance was better. This proves that, zeolites by themselves can resist corrosion but not efficiently, while in presence of zinc phosphate and owing to a synergistic effect between them, the performance was better. This opens the way to partial replacement of zinc phosphate with another safer and cheaper ingredient, which is zeolite.

The three zeolites can be applied in many industries besides the paint industry, such as reinforcing filler in rubber, plastics and ceramic composites, also can be applied in paper filling, paper coatings and electrical insulation.

The three zeolites are environmentally friendly materials that can partially replace other expensive anticorrosive pigments (e.g. zinc phosphate).

A new method for modifying the properties of aluminium oxide had been developed which allowed alumina to be used as a white, reinforcing filler in various rubber composites to replace carbon black, producing high performance white rubber vulcanizates comparable to those loaded with carbon black that could be coloured if needed.

Alumina was treated with small amounts of ammonium molybdate. Characterisation of modified aluminium oxide was carried out using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Also, evaluation of the pigments prepared, in terms of oil absorption, specific gravity, and bulking value using international standard testing methods was performed. The morphology of the natural rubber composites loaded with the new modified alumina were studied using SEM. Kraus equation was used to analyse the extent of polymer‐pigment interaction, while Mooney‐Rivlin relation was employed to study the near equilibrium stress‐strain behaviour.

The results showed that, the pigment had a significant effect on the rheological characteristics (scorch, cure time, etc.), mechanical properties, stress and strain at yield and at rupture of white rubber vulcanizates prepared resulting in high performance.

As concentration of molybdenum oxide increased in the alumina crystals, the reinforcing effect in rubber composites also increased till an optimum concentration where such a reinforcing effect reversed. However, investigation of the application of these pigments in other systems such as an anticorrosive pigment in paint formulations and reinforcing filler in polyester composites could also be interesting.

The pigments prepared could be used as reinforcing filler in plastic composites and also as anticorrosive pigment in paint formulations.

Aluminium oxide is a cheap compound. The originality of the work lay in the finding that by adding trace amounts of molybdenym to it, aluminium oxide's properties changed dramatically resulting in more effective action in reinforcing rubber composites filled with such modified alumina, producing white rubber composites with comparable properties to those loaded with carbon black, and may exceed them in some cases. This allowed the preparation of coloured rubber with good rheological and physical properties.

Organic coatings remain the most widely used way of protecting steel structures from corrosion. Traditional anticorrosive paints contain lead or hexavalent chromium compounds as active pigments. The use of these classical chromates is nowadays restricted by increasing environmental awareness and stringent national and international regulations. An alternative is the use of ion‐exchangeable pigments. The purpose of this paper is to show that cation‐exchanged zeolites can be considered as a safe and efficient alternative to traditional hazardous pigments in protecting steel surfaces.

The new pigments were characterised using different analytical and spectro‐photometric techniques. Characterisation of these pigments using X‐ray diffraction and scanning electron microscopy were done. X‐ray fluorescence was employed to elucidate the concentration of different elements in the prepared pigments. Evaluation of the ion‐exchanged and initial zeolite pigments using international standard testing methods (ASTM) was estimated. Testing the anticorrosive protection of cation‐exchanged zeolites in alkyd paints formulated based on their pigment volume concentration/critical pigment volume concentration was studied, and then these new pigments were applied on cold‐rolled steel panels. 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 tested.

The results of this work revealed that paint films containing initial Na‐zeolite performed the least protection behaviour, while films including Zn, Ca and Mg‐zeolites were better in their corrosion protection performance, and they can be arranged as Zn‐zeolite>Ca‐zeolite>Mg‐zeolite.

These pigments can be applied in other polymer composites, e.g. rubber and plastics as reinforcing agent and fillers.

The paper shows that these prepared pigments are environmentally friendly pigments which impart high anticorrosive behaviour to paint films with great economic savings.

The purpose of this paper is to determine a new easy route to obtain high performance and economic anticorrosive hybrid pigments based on kaolin and ferrite. The new route is based on depositing a surface layer of an expensive efficient anticorrosive pigment (ferrite) on a bulk of cheap extender pigment (kaolin). The combination of these pigments can add improved properties to the new pigment different from each of its individual components. These improved properties lead to imparting new properties to paint films containing these prepared pigments.

The new prepared hybrid pigments contain different concentrations of deposited ferrite on kaolin surface, are determined using X‐ray fluorescence analysis to estimate the concentration of each element in the pigments. The pigments are characterised using different spectro‐photometric and analytical methods to prove the deposition of the shell layer and elucidate the structure of their particles. Then, they are incorporated in anticorrosive paint formulations, where their presence in these formulations is between 50 and 75 per cent of the total pigments in the paint formula. A model of the mechanism of protection to the metal substrate is presented.

The results show that the presence of these hybrid pigments imparts excellent corrosion protection to steel substrates, in spite of their different concentrations and loadings in the paint films.

These pigments can be applied in other polymer composites, e.g. rubber and plastics as filler and reinforcing agent.

Prepared pigments are eco‐friendly and can replace other hazardous pigments (e.g. chromates) – also it can replace original ferrite pigments. These pigments can compensate for the presence of other known pigments in markets successfully. The main advantage of these pigments is that they combine both the properties of their counter‐parts, and they are of lower cost than the original inhibitive pigment (ferrite). Also, they can be applied in other industries other than paints, e.g. paper, rubber and plastics composites.

Kaolin is a soft, white mineral mainly composed of coarse‐ to fine‐grained, plate‐like aluminum silicate particles. As kaolin assists with desired rheological properties that help maintain proper dispersion and provide bulk to the product, it is used as an important extender in paint manufacture. It can be used to reduce the amount of expensive pigments, such as titanium dioxide. In spite of these uses, kaolin has the disadvantage of having coarse particles and low hiding power. The purpose of this paper is to introduce a new class of pigments based on kaolin as a core and titanium dioxide as the shell.

In the work reported in this paper, kaolin was used as a core covered with a surface layer of titanium dioxide comprising the shell in order to combine their properties and get over kaolin's disadvantages, besides enhancing its corrosion protection properties. The pigments prepared were characterised using X‐ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Deposition of titanium dioxide on the surface of kaolin was confirmed by Energy‐dispersive X‐ray analysis (EDAX) and X‐ray fluorescence (XRF) techniques. Pigment properties were estimated according to American standard testing methods (ASTM) methods and then were incorporated in anticorrosive paint formulations based on medium oil alkyd resin. The physico‐mechanical and corrosion properties of dry paint films were determined according to ASTM methods.

The tests revealed that the concentration of titanium dioxide layer deposited on kaolin surface was inversely proportional to the anticorrosive behaviour of these pigments.

The pigments can be applied in other polymer composites, e.g. rubber and plastics as filler and reinforcing agent.

The pigments prepared are eco‐friendly that can replace other expensive pigments. These pigments can compensate for the presence of titanium dioxide in paint formulations successfully, and thus lower the costs. The main advantage of these pigments is that they combine the properties of both of their counterparts, they are of lower cost, and they also overcome the disadvantages of both its counterparts, e.g. low hiding power of kaolin, photochemical activity of titanium dioxide. Also, they can be applied in other industries other than paints, e.g. paper, rubber and plastics composites.

The purpose of this paper is to introduce a new method of pigment preparation, which is economic and highly efficient in corrosion protection properties, known as the core‐shell method. According to this method, a cheap core (an extender) is covered with only a surface layer of effective pigments. Following this method of preparation, a new group of pigments is prepared in this research using the Egyptian kaolin ore as the core covered with single and mixed zinc, magnesium, and zinc‐magnesium phosphates as a shell to replace the original phosphates. These new pigments combine the properties of both its core and shell counter‐parts exhibiting improved corrosion protection properties that exceed both of kaolin and zinc phosphate individually.

Pigments concerned in this paper are prepared using simple chemical techniques, and then they are characterised using X‐ray diffraction, scanning electron microscopy combined with energy‐dispersive X‐ray analysis, and transmission electron microscopy. These pigments are incorporated in solvent‐based paint formulations based on medium oil alkyd resin. The physico‐mechanical properties of dry films and their corrosion properties are tested using accelerated laboratory test in 3.5 percent NaCl for 28 days, according to ASTM.

The prepared kaolin‐phosphate (core‐shell) pigments are based essentially on Egyptian kaolin ore, which is an abundant cheap ore in Egypt, and then the kaolin is covered with a surface layer of phosphates that are proved to be efficient anticorrosive pigments. These pigments are easily prepared, economically feasible and can successfully replace ordinary phosphate pigments with superior corrosion protection behaviour.

These pigments can be applied in other polymer composites, e.g. rubber and plastics as reinforcing agent.

Prepared pigments are environmentally friendly and can replace hazardous pigments (e.g. chromates) and ordinary phosphates. The main advantages of these pigments are that they combine both the properties of their core and shell counter‐parts, and they are of lower cost with similar and maybe in some cases better efficiency in corrosion protection of metals. Also, they can be applied in industries other than paints, e.g. paper, rubber and plastics composites.

The purpose of this paper is to investigate the anticorrosive effects of a new pigment based on bulk of talc covered with a surface layer of titanium dioxide.

The new pigments were characterized using different analytical and spectro‐photometric techniques. Characterization of these pigments using X‐ray diffraction, scanning electron microscopy and transmission electron microscopy. The energy‐dispersive X‐ray analysis technique was used to assure the presence of titanium dioxide on talc surface, then X‐ray fluorescence (XRF) was employed to elucidate the concentration of different elements in the prepared pigments. Evaluation of these pigments was undertaken using international standard testing methods. The pigments were then incorporated in solvent‐based paint formulations based on medium oil alkyd resin. The physico‐mechanical properties of dry films and their corrosion properties were tested using accelerated laboratory tests in 3.5 percent NaCl for 28 days.

The results of this work reveal that as the layer of titanium dioxide is increased in thickness, enhanced anticorrosive properties of the new pigments are obtained.

These pigments can be applied in other polymer composites, e.g. rubber and plastics, as a reinforcing agent.

These prepared pigments are environmentally friendly and impart high anticorrosive behavior to paint films, a unique homogenous texture, and deliver concomitant cost savings.

Aims to study inhibitive properties of new compounds that are based on the Wurtzite structure of zinc oxide with an admixture of cobalt using zinc oxide as a reference.

The conditions for the preparation of pigments using different ratios of both cobalt and zinc were investigated. Characterization of these pigments was carried out using spectroscopic methods of analysis via X‐ray diffraction, transmission and scanning electron microscopy. Also, evaluations 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 percent NaCl solution for 28 days. Electrochemical measurements based on corrosion rates of paint films also were studied.

The results showed that the anticorrosive protection properties of the pigment prepared were better than with zinc oxide pigment alone.

The pigments prepared can be used as reinforcing filler in different rubber and plastic composites providing them with an intense green color. As the concentration of cobalt oxide exceeds 15 percent, the reinforcing and effects decreased and vice versa.

Zinc chromate is one of the anticorrosive pigments most frequently used in the formulation of primers. However, its environmental aggressiveness and toxicity severely restrict its use and different green alternatives have been proposed in order to replace it. One such alternative is the pigment evaluated in this paper. New pigment applications, such as reinforcing fillers for rubber and plastic composites, also could be attractive.

The search for new techniques to teach English nowadays has been more than ever. These techniques have to be interesting and enjoyable in order to lower the anxiety levels of students when learning English (Bakhsh, 2016). That is why many scholars and teachers look forward to integrating technology into language teaching. Social media platforms (SMPs) are among these techniques since millions of people around the world utilize them for daily interaction. Yet, teaching English for specific purposes (ESPs) relies on learners’ needs and employs an eclectic approach in delivering its course content. For this reason, the current study reviewed articles that tackled the topic of teaching or learning ESP from SMPs so as to uncover their effect and the attitude or motivation of learners.

The researchers used the PRISMA flowchart model in order to identify, screen and include articles in the study.

The results revealed that SMPs are effective in teaching and learning ESP writing, speaking and vocabulary. Yet, the included studies showed that learners’ attitude toward SMPs is positive as they believe that they are motivating and interesting.

Some aspects of social media have turned out to be beneficial in the learning process and they need further investigation from ESP practitioners and scholars.

According to the study, it is crystal clear that the various social networks and platforms are beneficial and helpful for improving ESP productive skills.