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Water soluble alkyds were prepared from phthalic anhydride, maleic anhydride, trimellitic anhydride and maleopimaric acid separately by monoglyceride process. Pigmented electro coating compositions were prepared from water soluble alkyd resin, red oxide of iron and zinc phosphate. The anodic electrodeposition parameters such as voltage, time, solid content and pH were optimised. The mechanical and chemical properties of different electrocoating compositions were studied. The coating compositions prepared from water soluble alkyd resin based in maleopimaric acid showed good mechanical and chemical properties.

In surface coatings, no single resin binder possesses all the desirable properties. It is, therefore, a general practice to blend different polymers or copolymers having suitable complimentary properties in order to get the desired film characteristics provided that the blended polymers are compatible with each other. Hence, a wide range of performance characteristics can be achieved by blending.

The modification of jute fiber with acetic (aliphatic) and phthalic (aromatic) anhydrides has revealed pronounced improvement of the inherent drawbacks (such as breaking strength, thermal stability, color fastness, etc.) of jute fiber. Between the acetic anhydride (AA) and phthalic anhydride (PA) modified fibers, the latter have shown better improvement of the described properties. Modification of jute with anhydrides is carried out in an aqueous medium (solid-liquid system) with potassium persulfate as the initiator under the catalytic influence of ferrous sulfate (FeSO4). At an optimized reaction condition, the percent weight gain and efficiency of the modifying agents are 12.94% and 14.38% for AA respectively and 15.18% and 18.98% for PA respectively. The FT-IR spectra confirm the modification reaction and the TGA shows an improvement in the thermal properties. The mechanical properties are investigated with a tensile tester. Upon prolonged exposure of the modified fibers to sunlight, the color fastness of the modified and unmodified fibers is measured with a grey scale.

The commercial success of electro‐deposition of aqueous coating is mainly concerned with the development of water‐soluble film forming polymers. The field of these water‐soluble polymer systems for surface coating application is growing rapidly and expanding vigorously and they are destined to play a leading role in the near future. This may be mainly attributed to regulations on emissions, environment and ecology. In doing so, the electrodeposition technique offers a remarkable assistance to these systems at comparatively low cost, low energy requirement and high utilization efficiency. Research workers have done work on water‐soluble alkyds, epoxies and acrylics.

Fire retardant alkyd resins modified with dehydrated caster oil were prepared directly without going though the alcoholysis step. The method is based upon dehydrating castor oil with trimellitic anhydride. The oil thus produced contains sufficient combined carboxyl groups capable of polyesterifications with triols and glycerol or chlorinated monocyclic acetal and glycerol, and the macro‐structure is completed by further reaction with PA or chlorendic anhydride to obtain flame retardant resins. Melamine formaldhyde resin have been used in combination with the previous alkyd resins to improve hardness and also fire retardancy.

For conservation of petochemical solvents and reduction of air pollution, the water soluble polymers will play an important role in surface coating industry. The coatings based on water soluble polymers are thinned with water instead of petroleum solvent. Basically, the water based coatings may be made from oils, alkyds, polyesters, aminoes, phenolics, epoxies and acrylics. In spite of a large number of other synthetic resins being available for use in coating formulations, the alkyd resins surpass all of them in versatility, and low cost; combining a broad spectrum of performance properties with economy. Water soluble alkyd resins are similar to their solvent borne counterparts. The major difference is that their formulation is modified to introduce pendant carboxylic acid groups along the polymer backbone. These pendant acid groups can be neutralised with basic compounds to produce water solubility. Several workers studied preparation and evaluation of film characteristics of water soluble alkyd resins using various types of polybasic acids, polyhydric alcohols and fatty acids. The curing of these resins has been satisfactorily accomplished by stoving in presence of water soluble amino resins.

Epoxy resins are compounds which contain in their molecule more than one 1,2 epoxy group capable of undergoing polyreactions, referred to as curing reactions. The presence of epoxy groups may be either internal, terminal or on cyclic structures. Polyreactions take place at varying temperatures from low room temperature cure to high temperature cure systems upon addition of curing agents such as amines, amides or carboxylic acid anhydrides. The uncured resins which range from low viscosity liquids to high melting solids, soluble in organic solvents, become insoluble, infusible hard materials on curing due to crosslinked structure of the cured products.

The acute shortage coupled with tremendous increase in cost of various solvents used by paint industry and pollution becoming a serious concern has resulted in intensive study of water‐borne coatings. Water‐borne coatings ideally meet the needs for coating systems which do not cause atmospheric pollutions and at the same time help in conservation of precious and renewable petroleum resources. Many research workers have developed water‐soluble epoxies, alkyds and acrylics to make water‐based surface coatings.

To convert the post‐production polyethylene terephthalate (PET)‐containing fabrics waste into new value‐added polymeric materials using maleic anhydride grafted linear low‐density polyethylene (LLDPE‐g‐MAH) for improved toughness and to optimise the results of such a modification.

For effective toughening, various blends were made of polyamide 6 (PA) and post‐production PET‐containing fabrics waste (PET) by incorporating different concentrations of maleic anhydride grafted, linear low‐density polyethylene (LLDPE‐g‐MAH). The reactions of LLDPE‐g‐MAH with blend components were studied by Fourier transformation infrared spectroscopy, solubility behaviour of the products in formic acid and rheological measurements. Blends investigated were prepared in a co‐rotating twin‐screw extruder and characterised by differential scanning calorimetry and scanning electron microscopy. The static tensile property and impact strength of the blends were also measured.

The modification of polyamide 6 and post‐production PET‐containing fabrics waste using LLDPE‐g‐MAH showed significant enhancement of impact and interfacial adhesion over the unmodified one. The modification caused a chemical linkage between LLDPE‐g‐MAH and blend components which led not only to forming PA‐co‐LLDPE‐g‐MAH‐co‐PET copolymers, but also to ensuring the intrinsically strong chemical bonds across LLDPE‐g‐MAH phase/PET phase/PA matrix interface, which was the main cause to the improved impact strength and interface adhesion. The optimum results were obtained at 10 per cent of LLDPE‐g‐MAH.

The post‐production PET‐containing fabrics waste used in the present context was defibrated before processing.

The method developed provided a simple and practical solution to recycling and improving the toughness of post‐production PET‐containing fabrics waste.

The method of recycling post‐production PET‐containing fabrics waste was novel and the new polymeric materials obtained could find numerous applications such as hybrid films, fibres and engineering polymers.

Water soluble epoxy resins were prepared from epoxy resin, linseed fatty acids, maleic anhydride, trimellitic anhydride, maleinised dehydrated castor oil and maleopimaric acid. Pigmented coating compositions for anodic electrodepositions were prepared from water soluble epoxy resins using red oxide of iron and zinc phosphate as pigment. The electrodeposition parameters such as voltage, time, solid content and pH value were optimised. The mechanical and chemical film properties of different electrocoating compositions were studied.