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Henning [Metal Finishing, 75, May (1977) p. 64] has compared water‐borne primers and water‐borne total systems for appliances with the corresponding solvent‐based compositions and concludes that high quality finishes are indeed available from water‐based compositions. The author points out that two types of water‐borne coatings are available. The more common emulsion type generally offers good properties and has less than five per cent of organic cosolvent. The water‐soluble or water‐dispersible coatings, on the other hand, generally have properties equal to solvent‐borne coatings but contain up to twenty per cent of organic cosolvent. Generally, the water‐soluble types are more readily applied. On the other hand, they invariably require baking whereas emulsion type coatings can, of course, be formulated for architectural or maintenance applications. Emulsion systems are more sensitive, however, to freezing than are the water‐soluble compositions.

The purpose of this paper is to synthesize anticorrosion pigments ZnFe₂O₄ from diverse raw materials of various shapes and size of primary particles.

Anticorrosion pigments were synthesized through a high‐temperature process during a solid phase. Zinc ferrites were prepared from hematite (α‐Fe₂O₃), goethite (α‐FeO.OH), magnetite (Fe₃O₄), and specularite (Fe₂O₃) entering into reaction with zinc oxide at temperatures ranging from 600 up to 1,100°C. The nature of the initial raw material, primarily the shape of its particles, affects the shape of the particles of the synthesized zinc ferrite. The formulated zinc ferrites had a rod‐shape, lamellar, and/or isometric shape. The shape of the particles of synthesized zinc ferrites was studied with regard to its effects on the mechanical and corrosion resistance of organic coatings. The obtained pigments were characterized by means of X‐ray diffraction analysis and scanning electron microscopy. The synthesized anticorrosion pigments were used to prepare epoxy coatings and water‐borne styrene‐acrylate coatings that were subjected to post‐application tests for physical‐mechanical properties and anticorrosion properties.

The shape of the particles was identified in the synthesized pigments. X‐ray diffraction analysis revealed the degree of precipitation and lattice parameters. All of the synthesized pigments had good anticorrosion efficiency in an epoxy and in styrene‐acrylate coatings. Compared with a commercially used anticorrosion pigment, their protective power in coatings was demonstrably stronger.

The synthesized pigments can be used conveniently in coatings protecting metal bases against corrosion.

The synthesis of zinc ferrites with different particle shapes for applications in anticorrosion coatings provides a new way of protecting metals against corrosion. Of benefit is the fact that the synthesized pigments do not contain any environmentally harmful substances.

The purpose of this paper is to study the curing mechanisms, anticorrosive properties and protective mechanisms of three kinds of amine curing agents applied in a new kind of light colored water‐borne epoxy antistatic anticorrosive paint.

Using light color‐conductive mica, titanium oxides and environmentally‐friendly anticorrosive pigments in the two‐component water‐borne epoxy system, the light colored water‐borne antistatic anticorrosive paint was prepared. The molecular structure and curing mechanisms of the curing agents was analyzed by Fourier transform infra‐red spectroscopy, and the influence of the curing agents on anticorrosive properties and protective mechanisms was studied by electrochemical impedance spectroscopy.

The paints cured by the modified amine curing agent possessed optimal integrated properties with a coating surface resistivity of 10⁶ Ω and the best anticorrosive performance.

A novel light colored water‐borne epoxy antistatic anticorrosive paint cured by the optimal curing agent could be used in corrosion protection for oil tanks to replace the traditional oil‐based antistatic anticorrosive paints.

The degradation of coatings is, of course, a major area of interest for paint chemists. One of the coatings that degrades, much to the consumer's despair, is automotive coatings. The degradation of an acrylic‐melamine, cross‐linked coating containing finely dispersed pigment, metallic flake, and other additives was studied by English and Spinelli (Organic Coatings and Applied Polymer Science Proceedings, preprints of papers presented by the Division of Organic Coatings and Plastics Chemistry at the American Chemical Society, 185th National Meeting, Seattle, Washington, March 20–25, 1983, p. 733) using diffuse reflectance infra‐red spectroscopy. They found that the degradation is facilitated near the surface by ultra‐violet light and that there is a cleavage of the nitrogen‐carbon bond on the methoxymethylamino moities. Much of the degradation appears to take place at the surface level and degradation of bonds does not lead to significant self‐condensation of the degraded materials. The authors indicate that they are currently using MMR techniques to identify the products of degradation.

The paper deals with comparison of aqueous polymer dispersions from the point of view of the application thereof to anticorrosive primers. The corrosion tests performed with the coatings formulated on various water‐borne binders indicate considerable differences in the protective coating function. The differences in binders are given by the chemical composition and also by the sizes of polymeric particles forming the binder.

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.

The paper followed the effect of associative thickeners on the viscosity profiles of two water‐borne binders. The acrylic dispersion and the alkyd emulsion were selected as representative binders for water‐borne coatings. The effect of associative thickeners based on the hydrophobically modified ethylene oxide‐urethane block copolymer on the binder system of water‐borne coatings. The synergic mechanism was confirmed by using the combined types of thickeners and the effect on the rheology of coatings at the phases of their production, storing, and applications.

The paper aims to discuss the evaluation of anti-corrosive efficiency of conducting polymer, polypyrrole in water borne epoxy-polyamine coatings.

Polypyrrole (PPy) is synthesised by chemical oxidative polymerisation. The synthesised PPy is characterised by employing FT-IR, XRD, SEM and EDX analysis. The coatings are formulated using water borne epoxy cross-linked with aliphatic polyamine adduct and the effect of PPy on corrosion prevention is studied. PPy was used as anti-corrosive pigment in concentration varying from 1 to 5 wt.%. In addition to anti-corrosive property; mechanical properties, chemical resistance and weathering properties of the coatings containing PPy are studied, thereby obtaining a wholesome data about the quality and performance of these coatings.

The result obtained through various tests showed that the coating with 1 and 2% PPy exhibited excellent weathering resistance, mechanical properties and improved chemical resistance. Higher percentage loading of PPy (beyond 3 per cent) proves to be disastrous, as extended percolation networks are formed which results in rapid intense corrosion leading to fast coating breakdown.

The anti-corrosion property of the coating can be tested by means of atmospheric exposure such as Florida test which produces a real time evaluation of the anti-corrosive nature of the coating at natural condition rather than accelerated weathering, thereby providing more reliable performance data for intended application purpose.

The results find application in anti-corrosive/performance paints for industrial application.

This research paper presents the results of anti-corrosion behaviour of PPy in water borne epoxy-polyamide coating. Based on this result, a highly effective anti-corrosive coating can be formulated by the addition of small percentage of PPy in combination with other conventional pigments, thereby enhancing corrosion protection. But care must be taken so as to avoid formation of extended percolation network of PPy which leads to rapid coating breakdown.

This study aims to discuss the modification and/or improvement of intumescent coating system by incorporating waterborne resin with an appropriate combination of flame-retardant additives and four different fillers, namely, TiO₂, Al(OH)₃, Mg(OH)₂ and CaCO₃.

Coating mixtures are characterized using the Bunsen burner, thermogravimetric analysis, limiting oxygen index, scanning electron microscope, static immersion bath, Fourier transform infrared and adhesion tester.

Results show that the combination of coating with CaCO₃ filler significantly improved fire protection performance because of its thick char layer and the equilibrium temperature being 264°C. Char layer showed a uniform dense foam structure on micrograph and this formulation had adhesion strength of 2.13 MPa, which indicates effectiveness of the interface adhesion on substrate. Conversely, the combination of coating with Al(OH)₃ exhibited highest oxygen index of 35 per cent, which resulted in excellent flammability resistance.

This paper discusses only the effect of mineral fillers on properties of intumescent coatings.

In the modern design of building infrastructure, fire safety is significant for the protection of human life and assets. The application of intumescent coating in buildings is currently practiced because of its effect on material flammability during a fire.

The analysis method to evaluate the performance of water-borne resin with different fillers is formulated, and it could be applied in all kinds of coatings and mixtures to be used as an effective fire protection system for steel constructions.