Publications by authors named "S N Riabov"

Green synthesis of silver-containing nanocomposites based on polylactide (PLA) was carried out in two ways. With the use of green tea extract, Ag ions were reduced to silver nanoparticles with their subsequent introduction into the PLA (mechanical method) and Ag ions were reduced in the polymer matrix of PLA-AgPalmitate (PLA-AgPalm) (in situ method). Structure, morphology and thermophysical properties of nanocomposites PLA-Ag were studied by FTIR spectroscopy, wide-angle X-ray scattering (WAXS), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) methods.

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Antimicrobial and antiviral nanocomposites based on polylactic acid (PLA) and chitosan were synthesized by a thermochemical reduction method of Ag ions in the PLA-Ag-chitosan polymer films. Features of the structural, morphological, thermophysical, antimicrobial, antiviral, and cytotoxic properties of PLA-Ag-chitosan nanocomposites were studied by X-ray diffraction (XRD), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and antiviral, antimicrobial, and cytotoxic studies. The effects of temperature and the duration of reduction of Ag ions on the structure of PLA-Ag-chitosan nanocomposites were established.

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The effect of the chemical structure of interpolyelectrolyte complexes (IPEC) based on polymers of natural origin (pectin-chitosan, pectin-cationic starch (starch), carboxymethylcellulose (CMC)-cationic β-cyclodextrin (β-CD), anionic starch (starch)-cationic starch (starch) on the structure, morphology, thermomechanical and antimicrobial properties of silver-containing nanocomposites obtained by thermochemical reduction of Ag ions in interpolyelectrolyte-metal complexes (IMC) was studied. Thermochemical reduction of Ag ions in the IMC bulk for 30 min at 150 °C led to formation of silver-containing nanocomposites and this fact was confirmed by wide-angle X-ray scattering method. Transmission electron microscopy showed that different sized of silver nanoparticles were formed depending on the chemical structure of IPEC.

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The objective of this work is to study the peculiarities of structural organization, morphology, thermomechanical, electrical and antimicrobial properties of nanocomposites based on pectin-polyethyleneimine interpolyelectrolyte complexes and silver nanoparticles in dependence on the type of reducing agent being applied for chemical reduction of silver ions in the interpolyelectrolyte-metal complexes. The average size of Ag nanoparticles is shown to be increased with decreasing of the activity of reducing agent (E) and equals to 3.8 nm, 4.

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The structural organization and thermomechanical properties of nanocomposites prepared from interpolyelectrolyte-metal complex (IMC) involving anionic polyelectrolyte, pectin and AgNO, and cationic polyelectrolyte, poly(4-vinylpyridine), have been investigated using the methods of wide- and small-angle X-ray scattering and thermomechanical analysis. It is established that chemical reduction of Ag ions in the IMC by sodium borohydride results in formation of the nanocomposite based on the "pectin-poly(4-vinylpyridine)" interpolyelectrolyte complex (IPEC) and Ag nanoparticles as well. At the same time, the level of nanocomposites' structural heterogeneity is substantially enhancing, while effective size of the heterogeneity regions decreases.

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