Volume 92, Nº 3 (2019)

Data on the phase diagram, thermodynamic properties, and electrochemical behavior of sodium-antimony alloys in molten and nonaqueous electrolytes are summarized and analyzed in connection with the prospects for using antimony and its alloys and compounds as anode materials in sodium-ion batteries and other chemical current sources containing sodium.

Enzymatic degradation of polymer-colloid dispersions of chitosan acetate and chitosan succinamide with silver iodide sols was studied. The enzymatic degradation rate both in solutions and in film samples decreases in the presence of charged particles of the lyophobic sol. This fact is due to the enzyme inhibition by silver ions and to changes in the conformational and supramolecular state of the polymers.

The copolymerization of 1,1,2-trichlorobuta-1,3-diene with peroxide-containing acrylates and methacrylates in bulk at different temperatures, process time and the ratio of initial monomers, as well as the effect of these parameters on the yield and composition of the copolymers was studied. The synthesized copolymers were used as coatings for fastening a non-stiffened steel cord with increased tensile strength and high corrosion resistance as compared to coatings based on a copolymer of 1,1,2-trichlorobuta-1,3-diene with methacrylic acid.

A new hybrid gas separation membrane was prepared from poly(2,6-dimethyl-1,4-phenylene oxide) modified with graft copolyimide with side poly(methyl methacrylate) chains. The changes in the membrane structure on introducing up to 15 wt % modifier were evaluated by atomic force microscopy and density measurements. The microphase separation in modified polyphenylene oxide films was demonstrated. Introduction of graft copolyimide leads to an increase in the density of the hybrid films. The gas transport properties of the membranes were evaluated for H₂, CO₂, O₂, O₄, and N₂. Introduction of up to 10 wt % modifier does not noticeably alter the permeability of the hybrid membranes to all the gases but increases the selectivity in gas separation.

Factors influencing the formation of dense and uniform films of stabilized zirconium oxide from alcohol-containing suspension precursors on anode substrates by dip coating technique, such as the microstructure of the initial electrolyte powder, deposition conditions, and suspension concentration, were studied. The optimum conditions (withdrawal velocity, suspension concentration, heat treatment conditions) for efficient deposition and forming of a ≈10 μm thick electrolyte film were determined experimentally.

Stability against a high-speed impact of textile laminates reinforced with aramid fabrics and layered metal-textile laminates composed of alternating metallic sheets and layers of an aramid textile laminate. Dependences of the stability of composites against a high-speed impact on the type of a reinforcing filler, binder, and structure of the material are presented. It is shown that aramid textile laminates based on VK-3 phenol-caoutchouc binder are advantageous and use of magnesium alloys as components for metal-textile laminates is promising.

New film-type composite systems containing an inorganic filler, graphene oxide, in the chitosan matrix were elaborated. The mechanical and sorption properties of the resulting chitosan/graphene oxide composites were examined in dependence on to the filler content. It was shown that insertion of graphene oxide makes chitosan films more stable in aqueous media and also considerably improves the mechanical and sorption properties of composites as compared with chitosan films.

Additives for diminishing the content of carbon monoxide in gases formed in regeneration of the cracking catalyst without noble metals were synthesized and tested. As additives of this kind can serve mixed oxides based on copper, cerium, magnesium, and aluminum and manganese oxide supported by gamma aluminum oxide. Additives based on mixed oxides possess a high acidity and do not impair the activity of the catalytic system in the cracking reactions. In the efficiency (89.7–95.5%) in lowering the content of carbon monoxide, mixed oxides based on copper and cerium are comparable with the platinum-based additive KO-10 (96.8%). The activity of the additive based on manganese oxide depends on the sample calcination temperature, with the maximum efficiency in lowering the content of carbon monoxide (88.0%) reached at temperatures of 850–920°C.

Some fundamental aspects of the aerosol-assisted chemical vapor deposition of carbon-containing nanoparticles from an aerosol of ortho-xylene are described, including the influence exerted by the pyrolysis temperature and flow rate of the carrier-gas on the size characteristics, structure, and composition of the products being formed. It was shown that the shape, size, and structure of particles are determined by processes occurring in the pyrolysis zone, and its temperature is the most important technological parameter, together with the residence time in the reaction zone of products formed in the decomposition of ortho-xylene. The results obtained are of practical importance and form a basis for development of technology and equipment for producing carboncontaining nanoparticles from an aerosol of ortho-xylene.

In order to create an effective sorption method for extracting uric acid from blood plasma, the dynamics of uric acid sorption by a granular molecular imprinted polymer sorbent based on 2-hydroxyethyl methacrylate and ethylene glycol dimethacrylate and its non-imprinted analog were investigated. The speed intervals of the mobile phase were determined, in which the equilibrium mode of the dynamics of sorption of uric acid on the molecularly imprinted sorbent MIS-40 is realized. The optimal mode of the dynamic sorption process on MIS-40 was determined, at which the degree of extraction of uric acid from saline solution was 60% and the selectivity coefficient was 2.08.

The nitration of hyperbranched polyglycidols was studied. It was confirmed that there is no destruction of the polymeric chain when the nitration reaction is performed. The influence exerted by the molecular mass of polyglycidols on the degree of substitution of hydroxy groups in polyglycidol by nitrate groups was determined. The dependences of the degree of substitution of hydroxy groups on the reaction conditions and duration were found. It was shown that the fundamental aspects found in the study can be used to synthesize polyglycidyl nitrates with controllable degree of substitution from polyglycidols with various molecular masses.