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The porosity parameters of samples containing Co2+, Co3+, and Fe3+ ions were studied using IR spectroscopy to confirm the binding mechanism of metal ions to a polyacrylonitrile matrix. The main decomposition products of an acidic dye during catalytic oxidation in aqueous solutions were determined.

Conditions are studied for the synthesis of water dispersions of polymer composites containing palladium and the possibility of their use for the fabrication of modified electrodes is estimated. Water dispersions of the polymer poly(3,4-ethylenedioxythiophene), including a polystyrene sulfate polyanion (PEDOT:PSS) and Pd particles, were obtained by the redox reaction of Pd(II) with the polymer. The electrochemical behavior of composite PEDOT:PSS/Pd films in the medium of a phosphate buffer solution with pH 6.86 is studied. It is shown that, in the presence of hydrazine in a phosphate buffer solution, one wave of hydrazine oxidation on metal inclusions, Pd particles, is observed on the electrode. Specific features of the process of hydrazine oxidation are studied and a possibility using the obtained material for the creation of an electrochemical sensor for hydrazine is demonstrated.

Studies of the solubility of chitin from North Sea shrimp shells in aqueous NaOH solutions with urea and thiourea additives showed that chitin was totally dissolved in aqueous NaOH (10%) + urea (5%) + thiourea (5%). A thermally reversible gel formed if the solutions were stored at room temperature. The structures of chitin films obtained from the solutions were studied using IR spectroscopy and x-ray diffraction.

The solubility of wood cellulose of various molecular weights in aqueous NaOH solutions with added urea and thiourea was studied with variable temperature, solvent composition, and sequence of dissolution stages. It was shown that cellulose of average degree of polymerization up to 500-600 dissolved. Thermally reversible gels formed in solutions held at 20°C for 2 d. The structural organization of cellulose-hydrate films prepared from the solutions was studied using IR spectroscopy and x-ray diffraction.

A method was suggested for studying protolytic equilibria via analyzing the mechanical behavior of a substance. The method was verified by high-precision density measurements (accurate to within 5 mg/L) for aqueous solutions of a number of organic and inorganic acids and organic bases. The numerical values of the dissociation constants and the values of the observed molar volumes of solvated ionized and neutral molecules were calculated using the experimentally obtained concentration dependence of the density of the aqueous solutions at 25°C.

The enthalpies of dissolution of fibroin in imidazole-based ionic liquids were determined, and the contribution of polymer crystal structure decomposition to the enthalpy of dissolution was estimated. The heat of mixing of imidazole ionic liquid with water was described.

Materials containing micro- and nanodisperse nickel particles in hydrated cellulose film have been obtained by diffusion reduction. The effect of various NaOH concentrations on the film structure, functional composition, and morphology; nickel ion reduction; and nanocomposite material formation has been studied by Fourier transform infrared spectrometry, wide-angle X-ray scattering, and scanning electron microscopy. Nickel content in the samples varies from 1.1 to 21.3% wt %.

A new differentiating medium for the study of prototropic equilibria is proposed: acetonitrile with a small addition of DMSO. From the dependence of the picric acid pKa on the content of DMSO in this medium the optimum composition of the mixture was found ensuring the stability of the pKa values with minimal addition of DSMO: 4 wt %. It was experimentally confirmed that the addition of water in an amount up to 0.1 wt % has virtually no effect on the measured pKa value in a mixture with the optimum composition.

Macroinitiators containing β-diketonate fragments were prepared by copolymerization of styrene with cobalt(II) 5-Formation and morphological characteristics of selenium-containing nanostructures formed by reduction of selenious acid with ascorbic acid in the presence of ionic or nonionic polymeric stabilizer in aqueous solutions were studied by methods of nonlinear optics and flow birefringence at widely varied selenium to polymer weight ratio in solution ν. The molecular weights, root-mean-square and hydrodynamic sizes, and mean density of the nanostructures were calculated, and the trends in variation of these quantities were compared.

1-Ethyl-3-methylimidazolium acetate absorbs up to 27% of water from air at room temperature with liberation of a large amount of heat, 11 kJ mol−1. Ions of the ionic liquid do not enter into chemical reaction with water but form a stable complex of ethylmethylimidazolium acetate with 12H2O molecules (EMIA·12H2O).

Experimental and calculated data on the effect of anion and cation structure on the dissolving power of ionic liquids based on imidazole toward the natural polymers cellulose, fibroin and keratin are presented.

The study conducted led to the following conclusions: — Ionic liquids based on the 1-butyl-3methylimidazolium cation are not solvents for most synthetic polymers, but dissolve natural polymers characterized by a large number of H bonds in the supramolecular structure up to high concentrations. — The dissolving power of IL based on the 1-butyl-3-methylimidazolium cation is a function of the nature of the anion and the value of the negative charge on its electron-donor sites: IL with an acetate anion dissolve natural polymers better than liquids with a chloride anion. — An increase in the length and number of hydrophobic alkyl radicals in the imidazolium cation increases the hydrophoby of the IL and is accompanied by a decrease in the dissolving power with respect to natural polymers. The charge distribution in the imidazolium cation is a function of the length and number of alkyl radicals, determines the strength of the cation—anion bond, and the dissolving power of the IL changes proportionally to this strength. — Incorporation of proton-donor diluents decreases the dipole moment and value of the negative charge of the IL anion, which results in loss of the dissolving power of the binary mixture. — Aprotic diluents can be incorporated in these IL, and the change in the dissolving power of the binary mixture will be a function of the donor capacity of the aprotic diluent: a smaller decrease in the dissolving power is observed for the binary mixture in which the diluent has a lower donor number and more weakly competes with the IL for formation of hydrogen bonds with the polymer.

The experimental and calculated data on the structure and properties of ionic liquids are presented. The prospects for their use as the solvents for natural polymers are considered.

Computer modeling of the geometry and electronic structure of the solvent and its complexes with water and cellobiose allowed: explaining the decrease in the dissolving power of an ionic liquid in the presence of water using data on the electronic structure of the molecules; determining the overall mechanism of solvation of cellulose by ionic liquids and other organic solvents; calculating the change in the energy information of a solvate complex of the elementary cellulose unit with 1-butyl-3-methylimidazolium chloride, which was-20.64 kcal/mole.

A matrix of microcrystalline cellulose was used as a nanoreactor for the reduction of Ni(II) ions with hydrazine dihydrochloride.

The interaction of dimethyl sulfoxide with N-methylmorpholine-N-oxide (NMMO) monohydrate was studied by the NMR relaxation method. The mobility of DMSO molecules in the presence of NMMO monohydrate decreases due to the formation of a hydrogen bond between the water molecule of the monohydrate and a DMSO molecule. At the same time, the mobility of protons in the NMMO monohydrate increases due to a decrease in the strength of the water-NMMO hydrogen bond.

Glucose enthalpies of solution in binary systems N-methylmorpholine N-oxide monohydrateaprotic solvent at 75°C are measured.