The anticorrosion environmentally friendly pigments based on synthetic zeolite and zinc and calcium phosphates were prepared by mechanochemical method. The surface morphology and chemical composition of the obtained pigments were determined by scanning electron microscopy and energy-dispersive X-ray spectroscopy, respectively. It was established that the modification of zeolite by phosphates of divalent metals causes a decrease in the particle size and an increase in the specific surface area of the obtained composite pigments. It was shown that the use of zeolite/phosphate pigments increases the corrosion resistance of the aluminium alloy in 0.1% aqueous NaCl solution. The addition of complex zeolite/phosphate pigments to the sodium chloride solution decelerates the anodic process of electrochemical corrosion, which indicates the formation of a protective film on the metal surface. The composite pigment zeolite/Zn(H2PO4)2 exhibited the highest anticorrosive effect. A gradual release of the inhibitory components from these environmentally friendly pigments provides their long-term action to protect metal products.

UDC 620.193 Zinc phosphate nanoparticles with a thickness of ∼ 20 nm are synthesized by an ion-exchange reaction. We study the influence of the nature of reaction media and modifiers of the surface on their shapes and sizes. It is shown that acryl monomers are optimal modifiers of the surface. We investigate the anticorrosion activity of synthesized nanosized zinc phosphate in alkyd coatings on aluminum alloys by the method of electrochemical impedance spectroscopy. It is shown that nanosized zinc phosphate has better inhibiting properties than modified phosphate pigments and can be used in paint primer coatings.Corrosion-resistant paint coatings are extensively used for the protection of metallic structures against atmospheric corrosion. The primer layer containing inhibiting pigments plays the principal protective role in the composition of paint coatings formed on the metals. In this aspect, chromates prove to be especially efficient. However, they are extremely toxic and ecologically dangerous. At the same time, zinc phosphate is a wellknown nontoxic pigment [1, 2]. However, its anticorrosion efficiency is insufficient, especially in the initial stages of development of underfilm corrosion of the metal. This is explained by the low solubility of zinc phosphate in aqueous media. It was shown [3] that the corrosion resistance of primer paint coatings on aluminum alloys and galvanized steel increases as a result of the addition of micronized zinc phosphate instead of the phosphate pigment. This is probably caused by an increase in its specific surface area, inversely proportional to the size of particles of the pigment [4]. The anticorrosion activity of zinc phosphate in paint coatings can be increased by decreasing its particle sizes down to the nanorange. The methods used for the preparation of nanosized zinc phosphates were described in [5][6][7]. However, all these methods are power-consuming, technically complicated, and therefore, poorly applicable in the industry. The aim of the present work is to get nanosized zinc phosphate by using the improved procedures and study the influence of the conditions of synthesis on its size, shape, and anticorrosion properties. Materials and Methods for InvestigationsSynthesis of Nanozized Zinc Phosphate. We synthesized zinc phosphate in a glass reactor equipped with a mechanical stirrer at 20°С by an ion-exchange reaction in aqueous media. To modify the surface of obtained

Corrosion inhibition of aluminium alloy D16T by natural and calcium and zinc ion-exchanged zeolites and their compositions with phosphate pigment was studied. Clinoptilolite, a natural zeolite from Sokyrnytsia deposit (Transcarpathian region, Ukraine), has been used in this study as a basic component. Protective properties of polyurethane coatings containing ionexchanged zeolites were investigated in acid rain solution. Direct current polarization methods and electrochemical impedance spectroscopy were used. It was established that composition of zinc phosphate and calcium ion-exchanged zeolite has significant anti-corrosion synergistic effect because of deposition of protective film on aluminium alloy surface. The addition of phosphate/zeolite-inhibiting composition to polyurethane coating offers substantial increase of its protective properties in corrosion environment compared with the use of a single phosphate pigment.

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