Composite materials of Prussian Blue-polypyrrole (PB/PPy) were obtained via chemical redox process in mixed solution of iron (III), hexacyanoferrate (III), and pyrrole with chloride or nitrate supporting electrolyte. Synthesized composites in the form of a sedimented powder, or a film on the surface of Pt and ITO-coated glass, were characterized by various physical and electrochemical methods. Stability of PB/PPy films on Pt substrate was tested in electrocatalytic reaction of hydrogen peroxide reduction in weakly acidic medium (pH 6) as well as on ITO-coated glass substrate via electrochromic (spectroelectrochemical) measurements. Stability period of the amperometric response in 1 mM H 2 O 2 solution for films on Pt substrate synthesized in chloride media is 20 times longer than that of pure PB films obtained electrochemically in potentiostatic mode. Morphology of PB/PPy films has been found to depend on the composition of supporting electrolyte. Synthesis of PB/PPy composites in nitrate electrolyte leads to formation of a high-quality morphology, whereas PB/PPy films obtained in chloride solutions are cracked. In conformity with this observation, the stability period of the H 2 O 2 electroreduction for nitrate-synthesized films on Pt substrate was about 150 min, i.e., 80 times longer than that of pure Prussian Blue films without polymeric support and four times longer than that of chloride-synthesized films. Stability of the electrochromic response of PB/PPy films formed in nitrate media is 10 times higher than pure PB film.

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Improving the efficiency of greenhouses is one of the most promising directions in development of agriculture. New perspectives in this field opened up with the development of the new methods of synthesis of a new generation of photoluminescent materials based on colloidal semiconductor photoluminophores (so-called "quantum dots"). It is shown that use of the covering materials containing quantum dots can significantly increase yields. Moreover, introduction of these quantum dots into commercial production can significantly improve the mechanical properties of the covering films used for greenhouses and slow down the process of their destruction. The durability of greenhouse films increases from 1 to 3 years.

C URRENTLY, the biggest share of paints and varnishes intended for painting internal surface of metal canning containers is accounted for by compositions containing epoxy oligomers. Despite the fact that such materials allow to obtain coatings with good adhesion to metal substrates, sufficient chemical resistance and elasticity, they have one significant drawback, which is due to the main component of epoxy resins -bisphenol A. Due to the well-known negative effects of bisphenol A on human health, the use of such materials is currently limited.Promising replacement are composites based on polyester resins.However, it should be mentioned that the disadvantage of polyester varnishes intended for canning containers is the low resistance of coatings to sterilization when laying food products. The main reason for such low resistance is a relatively high proportion of ester groups, characterized by low water, alkali and limited acid resistance.To increase the resistance of such coatings, we proposed to introduce fragments of unsaturated monomers (capable of homopolymerization under the conditions of polyester compositions curing) into the composition of their polymer macromolecules. These fragments should create an additional steric hindrance for diffusion to ester groups of destructive molecules of aggressive media and ensure the durability of coatings in general.Synthesis of such polyesters is a typical polycondensation process, and to accelerate it, it is advisable to use various catalytic systems.

C URRENTLY, the biggest share of paints and varnishes intended for painting internal surface of metal canning containers is accounted for by compositions containing epoxy oligomers. Despite the fact that such materials allow to obtain coatings with good adhesion to metal substrates, sufficient chemical resistance and elasticity, they have one significant drawback, which is due to the main component of epoxy resins -bisphenol A. Due to the well-known negative effects of bisphenol A on human health, the use of such materials is currently limited. Promising replacement of these materials are composites based on polyester resins. However, it should be mentioned that the disadvantage of polyester varnishes intended for canning containers is the low resistance of coatings to sterilization when laying food products in containers. The main reason for such low resistance is a relatively high content of ester groups in the structure of these polymers, characterized by low water, alkali and limited acid resistance. To increase the resistance of such coatings, we proposed to introduce fragments of unsaturated monomers (capable of homopolymerization under the conditions of polyester compositions (intended for can-coating) curing) into the composition of their polymer macromolecules. These fragments should create an additional steric hindrance for diffusion to ester groups of destructive molecules of aggressive media and ensure the durability of coatings in general.Synthesis of such polyesters is a typical polycondensation process, and to accelerate it, it is advisable to use various catalytic systems.