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This article has been withdrawn as it was published elsewhere and accidentally duplicated. The original article can be seen here: 10.1108/eb043004. When citing the article, please cite: S.M. El-Sawy, F.A. Abdel Mohdy, M.A. Abd El-Ghaffar, (1993), “Highly efficient anticorrosive water-borne paints”, Pigment & Resin Technology, Vol. 22 Iss: 1, pp. 4 - 11.

Wood as a structural material has one feature which is unique among all structural materials; it is a crop which can be formed, whereas its competitors such as stone, brick, metal and plastic are all derived from exhaustible mineral sources.

Perfluoroheptyl methacrylate was copolymerized with acrylamide using different ratios of these monomers. The copolymers so obtained were methylolated with formaldehyde. The methylolated copolymers were used as multi‐purpose finishing agents for cotton. They impart oil and water repellence. Attachment of the methylolated copolymer to cotton is presumed to involve chemical bonds via reaction of the methylol groups of the copolymer and the hydroxy groups of cotton cellulose. This was evidenced by the wash‐fastness properties; no significant differences were noted in the oil/water repellence of cotton fabric treated with the copolymers in question.

Twenty seven formulations were prepared based on three grades of laboratory prepared silver pigments. These formulations could be classified into three main groups. The aim of this classification is to study the effect of the type of binder and pigment on the efficiency of the formulated electric conductive paints. A commercial silver conductive paint is used for comparison. The formulated paints were laboratory tested for adhesion, hardness, acid and alkali resistance, corrosion protection and electric conductivity. It has been found that these formulations pass all the laboratory tests. The conductivity of the formulated paints is higher than the conductivity of the commercial one. Both of the pigment particle size and the type of the used binder effect the conductivity of the formulated paints.

Some anticorrosive water‐borne paint formulations were prepared. These formulations based on zinc phosphate, zinc tetroxy chrornate and barium metaborate as inhibitive pigments with acrylate emulsions in absence and in presence of a water repellent type emulsion. The corrosion protective properties as well as the physico‐mechanical characteristics of painted films were studied and evaluated. Promising results were obtained which urge us to pay attention to the utilisation of these types of water‐borne paints from the point of view of econmy and safety.

Three different methods have been studied to prepare silver powder pigments in order to find out the most suitable product for application in conductive paints. X‐ray analysis, specific gravity, pH value, water solubility, oil absorption, particle size distribution, and particle shape of the prepared silver powders were measured and compared with a commercial pigment. It was found that two of the three grades of silver powders have more suitable properties for application as conductive pigments.

A water repellent fluorenated monomer was used in a mixture of monomers for treatment of pine wood samples, using both, impregnation and graft copolymerization methods. This resulted in obtaining a new wood‐based material, the properties of which are superior to those of the natural untreated one. The total polymer loading was generally low, but it was sufficient for improving the mechanical properties with an obvious decrease in the water uptake. Better results of bending strength can be obtained on treatment using the graft copolymerization technique, this can be attributed to the chemical bonding of the polymer with cellulose on grafting.

The chemical treatment of cotton fabric with bioallethrin to impart a toxic effect against mosquitoes is thoroughly investigated. The treatment is carried out either by an impregnation method or surface coating method. These fabrics are washed and stored, then tested against mosquitoes. A bioassay investigation, scanning electron microscopy examination, and testing for physico mechanical properties of the bioallethrin ∓ treated fabrics are performed. Additionally, we evaluate treated cotton fabrics with a polymer coating process designed to increase the wash durability and time of storage of bioallethrin ∓ treated fabrics.

Carbamoylethyl starch (CrES) and cyanoethyl starch (CES) were prepared by making use of the concept of the dry process under conditions which were developed to form the bases of environmentally sound (clean) technology. The obtained CrES and CES were saponified using alcoholic NaOH solution. The CrES and CES along with their saponified products were further modified by subjecting them to graft polymerization with Aam/AN mixture. Saponification of the so‐obtained grafted substances was also carried out. Presents the findings of these investigations which are explained in terms of structural changes in the starch, the ‐CN and CONH₂ groups, the Aam/AN polymeric graft and the site of attachment of the latter on the modified starch.

Starch/carboxymethylstarch‐poly (acrylonitrile, acrylamide, vinyl acetate) composites have been successfully prepared through polymerization of acrylonitrile, acrylamide or vinyl acetate with starch or carboxymethyl starch (CMS) using ceric‐ion type Ce^IV catalyst. The obtained composites were saponified using alcoholic KOH solution. Regardless of the composite used, results obtained led to the following: (a) enhancement of solubility percent as compared with starch and CMS; (b) the size removal reaches 100 percent for a given set of desizing condition used; (c) the tensile strength and elongation at break increase with sizing, while crease recovery decreases; (d) sizing treatment in the presence of the prepared composites gives positive influence on the abrasion resistance; and (e) incorporation of CMS in composite form in the sizing formulation exerts a considerable positive influence on the performance properties of the sized fabrics as compared with other sizing agents under investigation.