Volume 44, Nº 11 (2025)

The paper examines composite polymer materials based on a PVDF matrix, which differ in filler material. Polyvinylidene fluoride (PVDF) is an organic polymer material with a significant piezoelectric effect. Currently, due to its physical and chemical properties, it is actively used for the development and creation of acousto-electronic devices, including sensors for various purposes, as well as in flexible electronics devices. Using Raman spectroscopy and dielectric spectroscopy methods, it is shown that the electrophysical properties of a composite material based on PVDF are determined by the formulation and manufacturing conditions. The additional polarization of the PVDF composite with various fillers in an external electric field directly during the creation of samples will significantly improve the electrophysical properties (coefficient of electromechanical coupling, dielectric constant). At the same time, the use of solid-state fillers significantly improves the mechanical and operational properties of such composites.

Composite materials based on elastomeric matrices (chloroprene rubber of sulfur regulation and cold-cured polydimethylsiloxane) and magnetic fillers were obtained: hard magnetic (SmCo, NdFeB) and soft magnetic (natural magnetite Fe₃O₄, ZnNiCo ferrite) in the concentration range of 30–100 mass parts per 100 mass parts of the elastomeric matrix. The samples were molded both in the presence of a magnetic field up to 0.3 T and without it. As a result of studying the effect of structuring on the amplitude-frequency characteristics of the reflection coefficient (R) of samples in the frequency band 17.44–25.86 GHz, it was found that the amplitude and position of the of the attenuated R bands are determined by the composite formulation, and within the framework of one formulation, the anisotropy of the magnetization of the composite, which is determined by the nature of the distribution of the magnetic filler in the elastomeric matrix.

The article presents the results of studying the coatings formed using different methods by means of cold gas-dynamic spraying (CS) on the surface of structural steel St3. Various methods for forming protective polymer-containing coatings are proposed. The composition and morphology of the protective layers are studied using the SEM–EDS analysis method. The anticorrosive properties of the coated samples were studied using the electrochemical impedance spectroscopy and potentiodynamic polarization method during exposure to 3.5 wt.% NaCl solution. It is shown that the inclusion of superdispersed polytetrafluoroethylene (SPTFE) in the coating increases the corrosion resistance of the base copper-zinc layer. The best anticorrosive properties were established for a sample with a basic Cu-Zn CS layer annealed at 500 °C for 1 h, followed by SPTFE treatment and repeated annealing at 350 °C for 1 h. The obtained results indicate that polymer-containing coatings formed by the CS method effectively increase the protective properties of the treated material.

A comparative analysis of the structure and rheological behavior of thermoplastic vulcanizates based on polypropylene, ethylene-propylene-diene monomer and rubber powder was performed. Detailed structural studies of the compositions were carried out using atomic force microscopy. It was found that in mixtures containing rubber powder the polypropylene phase is enriched with carbon black particles with a diameter of about 100 nm. A study of the rheological behavior of thermoplastic vulcanizates showed an abnormal decrease in viscosity in mixtures containing up to 10 wt.% rubber powder. The critical parameters for the manifestation of this effect are: continuity of the PP matrix, nanoscale size of carbon black particles, their concentration and their uniform distribution in the PP matrix.

Artificial blood vessels made from fluoropolymer using electrospinning have high biocompatibility. They have unique combinations of strength, chemical resistance, and open interconnected porosity. This provides favourable conditions for endothelialization. The aim of this study is to investigate the structures and properties of these artificial vessels, formed from Russian fluoropolymer materials such as poly(tetrafluoroethylene), copolymers of vinidene fluoride and tetraflouroethylene, and polyvinylidenefluoroide. Depending on the fluoropolymer used, structural characteristics of vessel walls, surface free energies, strengths, elongations, and interactions with human mesenchymal stem cells are investigated. It has been demonstrated that a copolymer of vinidenedifluoride with tetraflouroethylene represents the most promising material for vessel manufacturing using electrospinning technology.

Disclosed is an approach to estimating uniformity distribution of a highly dispersed hybrid filler in the fibre-forming polymer matrix structure based on linearity of the dependence of variation of ohmic electrical resistance control. Influence of modes of technological stages of oriented fibres production on ordering of conducting clusters and on provision of high stability of electroconductive properties of oriented composite fibres is revealed.

Formulations of seven polyurea-based composite materials are proposed as a matrix to protect the inner surface of oil storage equipment from the formation of pyrophoric deposits. Mechanical or mechano-chemically activated mixtures of activated carbon with titanium dioxide and shungite with titanium dioxide were used as composite fillers. It has been established that the use of the developed composite coatings makes it possible to reduce the rate of hydrogen sulfide corrosion of steel by 26–70 times. It has been shown that coatings in which the filler is an ultrasound-treated mixture of titanium dioxide and activated carbon can perform not only a protective barrier function, but also provide oxidative desulfurization of oil vapor.