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In this work, we studied the formation and properties of copper nanoparticles obtained by chemical reduction of copper with tert-butylamine-borane in dilute aqueous solutions of polymers of various nature. Polyelectrolytes, nonionic and amphiphilic polymers were used as high molecular weight compounds. It was revealed that precipitates are formed in the composition of polyethylene oxide, but this polymer protects particles from oxidation. It was found that the smallest particles are formed in a solution of polyacrylic acid, but their resistance to oxidation is the lowest. Assuming poly-N- vinylpyrrolidone or polycations, sols with a particle size in the range from 3 to 12 nm are formed, which are stable to aggregation and oxidation for a long time. It is noted that nanoparticles obtained in solutions of amphiphilic polymers are most stable. [ABSTRACT FROM AUTHOR]

The work considered catalytic systems for chemical-thermal treatment of steel products. The characteristics and properties of systems including a copper-containing nanocomposite and various alloying elements (tungsten, nickel, chromium) have been studied. The possibility of using poly-N-vinylpyrrolidone as a polymer protector when combining copper-containing sols and some alloying metals has been shown. Investigations of the characteristics of the obtained samples were carried out using the methods of electron microscopy and electron spectroscopy. After applying the synthesis product to steel samples, thermal diffusion saturation was carried out in an ammonia medium. A metallographic study of these samples showed that processing using a catalytic system allows one to achieve higher values of microhardness and thickness of the diffusion layer than with conventional approaches to nitriding. It is noted that the increase in the efficiency of the process is associated with the introduction of copper-containing particles into the catalytic system. [ABSTRACT FROM AUTHOR]