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The purpose of this paper is to develop pyridine polyesteramide coatings from Linseed (Linum ussitatissimum) seeds oil for the utilisation of a sustainable resource as coating material, as well as to improve the coating properties.

Linseed oil was first converted into N,N bis 2‐hydroxyethyl linseed oil fatty amide (HELA). The resin was synthesized by the reaction of linseed oil fatty amide diol with 2,3‐pyridine di carboxylic acid to develop pyridine polyesteramide (Py‐PEA) and further treated with poly(styrene‐co‐maleic anhydride)(SMA) in different phr (part per hundred part of resin). The structural elucidation of Py‐PEA was carried out by FT‐IR, 1H‐NMR and 13C‐NMR spectral techniques. The thermal stability and curing behaviour of the resin were determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. The physico‐mechanical and anticorrosive properties were investigated by standard laboratory methods.

The authors developed a good anticorrosive coating material from sustainable resource. The physico‐mechanical and anticorrosive performance evaluation exhibited satisfactory results. The approach facilitated curing to occur at ambient temperature and the thermal studies revealed that Py‐PEA‐SMA‐45 might be safely used up to 140°C.

Poly(styrene‐co‐maleic anhydride) modified pyridine polyesteramide coatings showed the highest scratch hardness 3.0 kg, flexibility (1/8 inch canonical mandrel bend test) and gloss at 45° is 62‐64. Among all, Py‐PEA‐SMA 45 showed the best physico‐mechanical and chemical resistance performance. Thus, the resin may be used as an effective coating material.

The paper shows that the synthesis of polyesteramide resin from vegetable oil provides a new way to utilize a renewable resource based raw material.

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.

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.

Underwater shock wave loading has been implemented on various metals, foods and wood. The main goal of this study is to investigate the performance of unbleached jute fiber in terms of underwater shock wave loading and fiber surface parameters. The input short wave loading is varied by shock pressure. The underwater shock wave is generated by the explosion of a detonating fuse in the water tank. The process of bubble generation and expansion inside the water results in the formation of shock waves. After shock loading, jute fiber is taken for physico - mechanical and physico-chemical testing, such as those for breaking strength, elongation, moisture content, wicking, permeability, etc. The effects on jute fiber exposed by the underwater shock waves are also demonstrated by a scanning electron microscope (SEM). The maximum effect is observed at 100 MPa. Jute fiber treated by underwater shock waves shows improved moisture content and dye permeability than that of untreated jute fiber.

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.

The purpose of this study is to prepare core-shell ferrites/kaolin pigments and compare their efficiency in protecting metal substrates to original ferrites. The new pigments are based on precipitating a shell of different ferrites that comprise only 10-20 per cent of the whole pigment on kaolin (core), which is a cheap and abundant ore comprising 80-90 per cent of the prepared pigment. These new pigments combine the properties of both its core and shell counter-parts, exhibiting improved corrosion protection properties. Furthermore, the pigments are represented as efficient, economically feasible and eco-friendly with comparable efficiency to that of original ferrites in protecting steel substrates.

The new pigments were characterized using different analytical and spectrophotometric techniques, e.g. transmission electron microscopy, energy-dispersive X-ray analysis and X-ray fluorescence. The pigments were then incorporated in epoxy-based paint formulations. The physico-mechanical properties of dry films and their corrosion properties were tested using accelerated laboratory tests in 3.5 per cent NaCl for 28 days.

The results of this study revealed that ferrite/kaolin core-shell pigments performance was almost close to that of the ferrite pigments in the protection of steel, and, at the same time, they confirmed good physico-mechanical properties.

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

Ferrite and ferrite/kaolin are environmentally friendly pigments, and they can impart high anticorrosive behavior to paint films with concomitant cost savings.

The purpose of this paper is to study the effect of incorporating some inorganic fillers, namely aluminium oxide and aluminium hydroxide on the rheological, mechanical and thermal behaviour of acrylonitrile‐butadiene rubber (NBR) vulcanizates.

For improving physico‐mechanical properties of NBR vulcanizates, various compositions were made by incorporating different concentrations of employed fillers with NBR. These properties included the torque, cure time, tensile strength, elongation at break, swelling, diffusivity, as well as thermal behaviour of the loaded and unloaded NBR with fillers were characterised.

The incorporation of the two investigated fillers improves the thermal behaviour of the vulcanizates, especially aluminium hydroxide. All samples showed more or less a first order decomposition kinetics, for which the activation energy ranged from 177 to 187 kg/mol.

NBR is extensively used industrially for its single, most important property, which is an exceptional resistance to attack by oils and solvents. However, incorporation of fillers in (NBR) leads to the development of improved, competitive properties of the vulcanizate. A further study must be carried out on the flame retarding effect of the fillers, beside the effect of surface treatment of the fillers on the dispersibility and physico‐mechanical properties of the vulcanizates.

The use of two investigated fillers provided a simple and practical solution to improving the resistance to swelling in motor and break oil as well as the thermal behaviour of the NBR.

The use of these fillers was novel and could be used in many rubber industries especially in gasket and oil seals.

Evaluation of uracil and/or benzothiazol derivatives as antioxidants in natural rubber mixes.

Cyanoacetylurea 1, as a precursor, was prepared at a good yield from widely available, low‐cost chemicals. Compound 1 was treated with triethylorthoformate and amine derivatives in one pot reaction affording the target uracil derivative 3. Replacement of the cyano group in 1 by benzothiazol led to obtaining the interesting N‐hydroxy uracils containing benzothiazole moiety 5 at a good yield. Some of the compounds prepared was selected and were evaluated as antioxidants in natural rubber mixes. The rheometric characteristic of the compounded rubber and the physico‐mechanical properties of the vulcanizates were determined.

The cure rate index, tensile strength and modulus increased while the equilibrium swelling decreased, i.e. compound 5 behaved as a secondary accelerator. The rubber vulcanizates were subjected to thermal oxidative ageing at 90°C for up to seven days. It has been found that uracil and/or benzothiazol derivatives can protect natural rubber vulcanizates against oxidative deterioration.

The compounds prepareds were difficult to dissolve, they needed solvents with high boiling points, e.g. DMF, DMSO to be dissolved and even then they are not completely dissolved.

Uracil and or benzothiazol derivatives have many industrial applications.

The new compounds were prepared from very cheap and widely available chemicals. The compounds synthesised showed good antioxidant behaviour in comparison with the commercial antioxidant (phenyl‐β‐naphthyl amine) industrially used.

To evaluate the performance of a reactive diluent, nonylphenyl methacrylate (NPM) for toughness improvement of bisphenol‐a‐glycidyl dimethacrylate (BisGMA) and to optimise the results of such a modification.

To achieve desirable rheological and physico‐mechanical properties of BisGMA/NPM network, various compositions were made by incorporating different concentrations of NPM. The effect of concentration on the impact and the adhesive strengths of the unmodified and modified BisGMA networks were characterised.

The modification of BisGMA resin using NPM showed significant enhancement of the impact and the adhesive strengths over the unmodified one. The modification caused a chemical linkage between NPM and BisGMA resin, which led not only to a phase separation but also to establishing the intrinsically strong chemical bonds across the NPM phase/resin matrix interphase, which was responsible for the improvement of the impact and adhesive strength. The optimum results were obtained at 10/h (parts per 100 parts of BisGMA resin) of modifier.

The reactive diluent, used in the present context was synthesised from nonyl phenol, methacrylic acid and benzoyl chloride in methyl ethyl ketone using triethylamine as base.

The method of modification developed provides a simple and practical solution for improving the rheological and physico‐mechanical properties of BisGMA network.

The method developed is a novel one for enhancing the rheological and physico‐mechanical properties of BisGMA network diluted with NPM resin and may find numerous applications in surface coating and adhesive.

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.