Search

Using key publications, the review analyzes fundamental methods for synthesizing polymer biocides of varying chemical structure and discusses the mechanism behind the effect of the described formulations and their areas of application. High molecular weight compounds with inherent biocidal activity and opportunities for modification of polymers through chemical transformations or introduction of organic or inorganic additives are considered. The key focus of this review is on the analysis of approaches to the production of antibacterial coatings. Particular attention is given to the prospects of using cationic polyelectrolytes and metallopolymer compounds to which the resistance of pathogenic bacteria is not developed.

Due to the presence of cationic units interpolyelectrolyte complexes (IPECs) can be used as a universal basis for preparation of biocidal coatings on different surfaces. Metallopolymer nanocomposites were successfully synthesized in irradiated solutions of polyacrylic acid (PAA) and polyethylenimine (PEI), and dispersions of non-stoichiometric IPECs of PAA–PEI containing silver ions. The data from turbidimetric titration and dynamic light scattering showed that pH 6 is the optimal value for obtaining IPECs. Metal polymer complexes based on IPEC with a PAA/PEI ratio equal to 3/1 and 1/3 were selected for synthesis of nanocomposites due to their aggregative stability. Studies using methods of UV–VIS spectroscopy and TEM have demonstrated that the size and spatial organization of silver nanoparticles depend on the composition of polymer systems. The average sizes of nanoparticles are 5 nm and 20 nm for complexes with a molar ratio of PAA/PEI units equal to 3/1 and 1/3, respectively. The synthesized nanocomposites were applied to the glass surface and exhibited high antibacterial activity against both gram-positive (Staphylococcus aureus) and gram-negative bacteria (Salmonella). It is shown that IPEC-Ag coatings demonstrate significantly more pronounced biocidal activity not only in comparison with macromolecular complexes of PAA–PEI, but also coatings of PEI and PEI based nanocomposites.

Tuning the size and structure of bimetallic nanostructures is for the design of functional compounds with desirable properties. In this paper, the mechanisms that control radiation-induced assembly of bimetallic core–shell nanoparticles in polyelectrolyte matrices are discussed. The stages of Ag/Cu nanoparticle formation in the films of poly­(acrylic acid)–poly­(ethylenimine) complexes have been studied for the first time using X-ray diffraction analysis including synchrotron techniques combined with electron microscopy. The generation of silver nanostructures proceeds via their parallel nucleation and growth during the entire process of bimetallic nanoparticles formation. The sizes of shells are controlled by the competition between the growth of silver nanostructures and the formation of shells. Copper shells are generated in two stages: (1) ultrasmall nanostructures, which are slowly formed at the first stage, prevent the growth of silver nuclei; (2) as the shell improves, the growth rate of copper nanostructures increases dramatically. The results obtained demonstrate the possibility of single-stage controllable radiation-initiated synthesis of core–shell bimetallic nanoparticles directly in interpolyelectrolyte films.

Copper, silver and gold nanoparticles were obtained by reduction of metal ions under X-ray irradiation of “layer-by-layer” (LbL) coatings in a water-alcohol medium. The precursors for metal polymer composites (metallopolymer complexes) were prepared by sorption of metal ions in polyethyleneimine - poly (styrenesulfonic acid) and polyethyleneimine - poly (acrylic acid) coatings deposited on cotton fibers. EPR spectroscopy was use to characterize the complexation of metal ions in coatings with different chemical structure and variable number of polyanion-polycation layers. The effect of coating structure and thickness on the size and stability of nanoparticles was studied using TEM and microdiffraction measurements. Antibacterial activity was found for composites containing silver nanoparticles. The reported study was funded by RFBR according to the research project № 18-33-01155.

The article presents the results of a study of various rubber compounds based on rubbers containing, in the composition, made by FGUP GosNIIOHT diafen FP, sulfenamide C and N,N'-dithiodimorpholine instead of imported analogues. Rubber compounds were made on a laboratory rubber mixer SKI-3L with Intermix rotors. After a day at room temperature, the rubber mixtures were vulcanized on a vacuum compression machine of column type a firm Panstone 3RT. The main technological indicators of rubber mixtures after their manufacture on the rolls were: ductility, ring modulus and density. These indicators characterize the processability of rubber mixtures in the manufacture of products from them. For the obtained vulcanizates, the elastic-deformation properties (conditional tensile strength, relative elongation at break, Shore A and ISO hardness, bond strength with metal at tearing, and abrasion resistance) were determined by standard methods. To assess the performance properties of rubbers, changes in conditional tensile strength, relative elongation at break, hardness, volume and mass after rubbers aging in corrosive media, as well as relative residual deformation of compression, temperature limit of brittleness and frost resistance were determined. The possibility of using diaphene FP, sulfenamide C and N,N'-dithiodimorpholine made by FSUE "GosNIIOHT" as part of various rubber mixtures instead of imported analogs is shown. The obtained rubbers according to the technological, elastic-deformation and operational properties comply with the requirements. These rubbers can be used for the manufacture of rubber-technical products with a special set of elastic-deformation and performance properties, and domestic ingredients manufactured by the Federal State Unitary Enterprise GosNIIOHT can be introduced into production.

The bimetallic nanostructures are of considerable interest for various prospective applications. This paper reports a generation of the Cu/Ag and Cu/Au nanoparticles in the interpolyelectrolyte films irradiated in aqueous media. It was shown that the radiation-induced reduction of (Cu/Ag) or (Cu/Au) ions in the matrix of poly(acrylic acid)-polyethylenimine complexes led to formation of the nanoparticles with narrow size distribution. The core-shell structure of nanoparticles was demonstrated by the TEM results. According to the X-ray diffraction data, the nanoparticle cores (Ag or Au) are formed at early stage of irradiation, while increase of the absorbed dose results in the growth of copper shell. It was demonstrated that the radiation-induced reduction could be applied for effective preparation of bimetallic nanoparticles directly in the polymer matrix.