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Composite nanoparticles with a core consisting of associated anatase crystallites and a polymeric shell consisting of poly(N-vinylpyrrolidone) or poly(N-vinylcaprolactam) were synthesized and found to have antimicrobial activity against Escherichia coli and Staphylococcus aureus as well as photocatalytic activity in decomposition of methyl orange and methylene blue dyes. The highest antibacterial activity of the particles with poly(N-vinylpyrrolidone) shell is due to the larger amount of S O 4 2 − groups and water adsorbed on the surface, while their photocatalytic activity is comparable with that of commercial nanoanatase samples.

Nanocomposites based on poly(N-vinylcaprolactam) containing functional nano-anatase particles were produced by mixing and mechanical grinding of mixtures of poly(N-vinylcaprolactam) and Hombifine N (nano-anatase) powders in a porcelain mortar (method 1) and by mechanical milling of the same powders using a high-energy planetary ball mill (method 2). Differences in the diffraction patterns of nanocomposites prepared by method 1 (partial crystallization and an amorphization of nano-anatase particles in the nano-anatase/poly(N-vinylcaprolactam) composite) and method 2 (amorphization of nano-anatase particles) were found. An increase in the X-ray intensity was found to cause physical degradation of the polymer in nano-anatase/poly(N-vinylcaprolactam) composites depending on its prehistory. The preparation of nanocomposites by method 2 was shown to increase photocatalytic activity in the degradation of the dye methyl orange under ultraviolet light irradiation.

Hydrolysis of TiOSO4 · xH2SO4 · yH2O and TiOSO4 · xH2O, performed in the presence of poly-N-vinylcaprolactam (PVCL) or poly-N-vinylpyrrolidone (PVP) and in an aqueous medium, has provided for the first time samples containing nanophases of, respectively, η-modification of TiO2 – x · nH2O ( intercalates TiO2 – x · (nH2O, PVCL) or TiO2 – x · (nH2O, PVP)) and with anatase structure (TiO2). The samples have been characterized by X-ray diffraction and X-ray photoelectron spectroscopy. They are found to have different antimicrobial activities. A relationship is established between the antimicrobial activity and the structural features of titanium(IV) oxide; concentration of hydrated titanium dioxide in the samples; and the content of free water and hydroxyl and $${\text{SO}}_{4}^{{2 - }}$$ groups on the surface of anatase and η-phase nanoparticles, respectively. The choice of polymer does not affect the antimicrobial activity.

The interaction of microwave radiation with solid polyvinyl alcohol results in the structuring of the polymer accompanied by a change both in the contribution of competitive (both intra- and intermolecular) reactions and in the ratio of reaction products in comparison with the thermal reaction under the same conditions.