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The process of thermal-oxidative degradation of polymer materials has been studied on the example of polyethylene in the presence of quinones and / or nitroxyl radicals. The synergistic effect of the positive action of a mixture of stabilisers from a number of quinones and nitroxyl radicals on the destructive process of polyethylene has been established. It has been shown that the rate of degradation has significantly slowed down when an equimolecular mixture of 4-acetylamino-2,2,6,6-tetramethylhexahydropyridine-1-oxyl and 2,6-di-tert-amyl-1,4-cyclohexadienone inhibitors has been introduced into the polymer. The kinetics of the initiated thermo-destructive process of polyethylene oxidation in the presence and absence of stabilisers has been studied. A mechanism of joint action of stabilisers based on their interaction with radicals and the breakage of radical chains, as well as a mechanism for the regeneration of stabilisers, has been proposed.

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The article presents the results of investigates of the effect of ultrafine additives (zirconium diboride, silicon carbide, diamond) on the physical and mechanical properties of composite electrochemical nickel deposits obtained from colloid-electrolyte baths. It was revealed that the most effective nanostructured additives are zirconium diboride and ultrafine diamond. Current efficiency and potentiostatic researches shew mutual participation of finely dispersed nickel hydroxide compounds in the formation of a composite electrochemical deposits and dispersed phase of zirconium diboride or ultrafine diamond that are attendant in the solution or formed during electrolysis and introduced into the electrolyte. It is shown that the optimal values of internal tensions and microhardness are associated with the hardening of the nickel matrix together with various nano-dispersed additives that are included in the deposit. These deposits can be used as an alternative to chrome deposits on parts of machinery.

From the point of view of "green chemistry", the relevance and prospects of the electrooxidation of organic compounds is confirmed by numerous scientific data on the practical use of methods developed and introduced into production for obtaining demanded chemical and pharmaceutical preparations. The advantages of electrochemical methods for converting organic substrates into products of low-tonnage chemical industry and pharmaceutical chemistry are shown. The reactions of electrooxidation of alcohol groups of synthetic and natural compounds, mediated by catalytic systems based on inexpensive TEMPO-like nitroxyl radicals, which provide numerous key synthetic advantages over other oxidation methods, are considered. It has been shown that oxidation reactions can be carried out under mild conditions, without the use of environmentally harmful reagents and toxic solvents, without large economic investments and with the maximum yield of high-purity target products with the formation of little or no waste. Further fundamental and technological research is recommended in order to develop effective electrocatalytic systems for use in industrial electrooxidation.