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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.

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.

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.

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.

Polybisphenol phthalate was synthesized and incorporated into linseed oil alkyd by replacing a part of phthalic anhydride during the preparation of alkyds. Film properties of these polybisphenol phthalate modified alkyds (also termed as copolyesters) were examined and compared with those of pure alkyds. Copolyesters were superior in film properties as compared to pure alkyd resins especially with respect to chemical resistance.

Considerable effort has been made by this Laboratory and industry to make polyfunctional derivatives of rosin through the introduction of different groups into the resin acid moiety.

Egyptian cotton straw powder was acid hydrolized in presence of coal tar phenols fraction (b.r. 170–185°C) to give the phenols‐furfural resin. Homopolyepoxy resin was prepared via condensation of epichlorohydrin with phenols‐furfural resin. Similarly copolyepoxy resin was also prepared from epichlorohyhdrin, phenols‐furfural resin and prepared bisphenol A based on coal tar phenols fraction. A study of curing these epoxy resins at 170–185°C with phthalic or maleic anhydride also curing at room temperature with amine was carried out. Also the effect of the addition of kaolin as a filler was investigated to find the optimum condition which allow the cured resin to act as wood adhesive. The obtained results were comparable with those of some commercial adhesives.

Polyesteramide resin based on the condensation of hydroxyethylamide derivatives of fatty acids of soybean {N, N′‐bis(2 hydroxyethyl)soybean amide} and various dibasic acid and anhydride were synthesized. Physico‐chemical characteristics and film forming properties of these resins were determined to prove its suitability as a vehicle for surface coatings. The study reveals that resins can be used for the baked type of finishes.

Hydroxy terminated polyesters were prepared by the reaction of tetrabromophthalic, phthalic, and maleic anhydrides with polyethylene glycol via melt condensation technique. They were characterized by hydroxy number, and intrinsic viscosity measurements. Also, the fire retardancy of polyesters was evaluated as varnish films on plywood strips. The polyesters were reacted with excess toluene ‐2, 4‐ diisocyanate to yeild isocyanate terminated prepolymers which were subsequently reacted with 5, 5‐ dihydroxymethyl‐2‐trichloro‐methyl‐1,3‐ dioxane or ethelene diamine. These polymers were characterized by Ir and ¹H NMR spectra, viscosity measurements, and thermogravimetric analysis.