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Surface of aluminium oxide was modified using the adsorption of stearic acid molecules from benzene solution. The adsorption isotherm and the sedimentation properties of the aluminium oxide in the organic medium were determined. Commercial unsaturated polyester was cured to a cross‐linked structure using styrene, methyl methacrylate and methyl acrylate monomers as cross‐linking agents, and small amounts of peroxidic initiator to initiate the curing process. Different composite materials of polyester‐modified surface aluminium oxide were prepared, and the physicomechanical properties of the prepared composites were measured for the products in the form of cast laminates and rods.

Rubber gaskets find wide applications in steel structures. Gaskets are usually used on the edges or on the nail hole positions. These are the weakest positions, where corrosion starts, whether the structure is protected by paint or by other methods. In this work, anticorrosive pigments were incorporated in rubber formulations. They are tested by corrosion protection when used as gaskets with steel panels. Results showed that the presence of anticorrosive pigments in rubber gaskets prevents early rusting under it in comparison with the blank. Zinc‐tetroxy chromate pigment exhibited the highest rust inhibiting power when chloroprene rubber formulations were used. The change of the pigment percent barely affect the quality of protection when syrenebutadiene rubber formulation were used. Zinc tetroxy chromate pigment improved the physico‐mechanical properties of chloroprene rubber under investigation. The used formulations can tolerate thermal oxidative aging at 90°C up to 8 days. The rate of vulcanization was not affected by increasing the concentration of the inhibitive pitments.

This paper aims to study the role of organobentonite (OB) as a filler to improve the mechanical strength of styrene butadiene rubber (SBR). Organoclay was first prepared by modifying bentonite with different concentrations of N-cetyl-N, N, N-triethyl ammonium bromide. A series of SBR composites reinforced with OB were prepared using master-batch method.

The curing characteristics, mechanical properties, thermal behavior, dielectric properties and morphology of SBR/OB composites were investigated.

The elastic modulus and tensile strength of composites were increased by inclusion of OB, while the elongation at break was decreased, due to the increase in the degree of cross-linking density. Thermal gravimetric analysis revealed an improvement in the thermal stability of the composite containing 0.5 cation exchange capacity (CEC) OB, while the scanning electron micrographs confirmed more homogenous distribution of 0.5CEC OB in the rubber matrix. Also, SBR/0.5CEC OB showed low relative permittivity and electrical insulating properties.

Bentonite has been recognized as a potentially useful filler in polymer matrix composites because of their high swelling capacity and plate morphology.

OB improves the cured rubber by increasing the tensile strength and the stiffness of the vulcanizate.

Using cheap clay in rubber industry lead to production of low cost products with high efficiency.

The clay represents a convenient source because of their environmental compatibility. The low cost and easy availability make the modified clay used as fillers in rubber matrices, and the resultant composites can be applied in variety industrial of applications such as automobile industries, shoe outsoles, packaging materials and construction engineering.

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.

The purpose of this paper is to evaluate the efficiency of organobentonite (OB) as reinforcing filler in acrylonitrile-butadiene rubber (NBR). The composites were prepared using different loadings of OB and studying in details their properties. A series of OB was modified using surfactant N-cetyl-N, N, N-trimethyl ammonium bromide (CTAB) with concentrations 0.5, 1 and 2 cation exchange capacity (CEC) of bentonite.

The different bentonites were characterized using different analytical and spectro-photometric techniques, such as infra red, X-ray diffraction, thermogravimetric analysis and scanning electron microscopy, while rubber vulcanizate rheological, morphological, swelling and thermal properties were examined using different standard instrumental testing and methods.

The study revealed that the modification of bentonite using CTAB showed significant enhancement on NBR properties, and the optimum filler loading was 12 phr for both 0.5CEC OB and 2CEC OB. These modified bentonites improved reinforcing properties to NBR vulcanizates. Also, results showed that composites exhibited remarkable improvements in tensile strength, elongation at break and hardness in the presence of modified bentonite and also an increase in thermal stability.

Na-B cannot be applied in rubber matrix without modification because it is incompatible with it.

The modified bentonite is considered as efficient reinforcing filler which can replace other fillers because it has lower surface energy and improved intercalating behaviour in rubber matrix.

These papered bentonites are cheap with relatively high purity, which make rubber/clay composites emerge as new class of material and can be used in different fields other than rubber.

Itaconic acid was reacted with phenylene diamine (ortho, meta and para) and o‐tolidine in boiling dekalin, using Dean and Stark apparatus. The polymers prepared were evaluated for their suitability as antioxidants for natural rubber vulcanizates. The amide polymers prepared showed high efficiency as antioxidants for rubber vulcanizates, exceeding the performance of commercial antioxidants. In addition, the results obtained are encouraging and support the use of these polymers from both the environmental and economical points of view.

This paper aims to express in detail the rheological, morphological and thermal properties of unpigmented and pigmented styrene-butadiene rubber composites with new prepared inorganic pigment based on kaolin covered with a thin layer of calcium and magnesium oxides or mixed oxide of both together. These new pigments combine the properties of both their constituents (kaolin and metal oxides), which are a new trend in inorganic pigments called core-shell pigments. The pigments used for comparison are kaolin (K), CaO/kaolin (CaO/K), MgO/kaolin (MgO/K) and CaO.MgO/kaolin (CaO.MgO/K).

The different pigments were characterized using different analytical and spectrophotometric techniques, such as X-ray diffraction, scanning electron microscopy/energy dispersive X-ray and transmission electron microscopy, while rubber vulcanizates' rheological, morphological, swelling and thermal properties were examined using different standard and instrumental testing and methods.

The study revealed that there is a significant effect of the new prepared pigments on SBR properties, where the optimum pigment loading was 40 phr for CaO/kaolin, while it was 2.5 phr for MgO/kaolin. Studying the effect of different ratios of oxides on kaolin (5, 10 and 20 per cent), different loadings of these pigments ranging between 2.5 and 40 phr were done for each pigment. These modified kaolin or core-shell metal oxide/kaolin pigments imparted new and improved reinforcing properties to SBR vulcanizates.

No research limitations were found.

Core-shell MgO/kaolin pigments are eco-friendly and can replace other expensive pigments that are usually used as fillers in the rubber industry with less expenses and comparable efficiency.

These new pigments are cheap and efficient and can be used in different fields other than rubber.

This paper aims to prepare alkyd protective paint by using modified alkyd with 3,6-dichloro benzo[b]thiophene-2-carbonyl glutamic acid (DCBTGA) as a source of dicarboxylic acid and evaluating their anticorrosive properties compared with those of unmodified alkyd coatings for steel protection.

Short, medium and long oil alkyds, which represented as (0, 10, 20 and 30% excess-OH) according to the resin constants (Patton, 1962), were prepared through a condensation polymerization reaction via a solvent process in a one-step reaction. The modification of alkyd was carried out by using DCBTGA as a source of dicarboxylic acid. The prepared modified alkyd was confirmed by IR and NMR spectral analysis. The physicochemical, mechanical and anticorrosion performance properties of the considered modified coating formulations against unmodified blank coating were studied to confirm their application efficiency.

The best results in terms of physicochemical, mechanical and anticorrosion performance properties were found according to the following of this order activity: 30 replacements of the modifier (DCBTGA) for each hydroxyl continent were 30% Ex-OH > 20% Ex-OH > 10% Ex-OH > 0% Ex-OH, compared with that formulation containing unmodified alkyd, especially with increasing the modifier percent.

The prepared DCBTGA-modified resins can be used for different applications based on the type of alkyd and application.

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 the paper is to examine the synthesis of polyaniline (PAn) and poly(m‐toluidine) (PmT) via an inverse emulsion polymerisation pathway and evaluate of the synthesised polymers as corrosion inhibitors for steel protection in surface coatings.

PAn and PmT were prepared by inverse emulsion polymerisation using ammonium persulphate as an initiator and sodium dodecylbenzene sulphonate (SDBS) as an emulsifier. Spectrophotometric measurements were conducted to characterise the prepared polymers. Latex paint formulations were prepared and dry paint films were evaluated for their physical, mechanical and corrosion protection performance.

The prepared conducting polymers of PAn and PmT are good candidates for enhancing the corrosion protection of steel. They showed good performance as corrosion inhibitors in latex paints without bad side effects on the physico‐mechanical properties of paint films.

Recent advances in corrosion protection of steel by coatings via inverse emulsion polymerisation of aniline and m‐toluidine have improved performance of anti‐corrosive water‐borne paints. Using formulations based on this new technology, offer uncompromised high performance eco‐friendly anti‐corrosive water‐borne systems that answer the future industrial demands from the economical and environmental points of view.

PAn and PmT prepared by inverse emulsion polymerisation showed promising results as corrosion inhibitors for steel protection. The polymerisation process was conducted in water (emulsion polymerisation) and the polymer lattices were incorporated in water borne paints from ecological and economical points of view.