STUDY OF WETTABILITY OF CARBON RODS BASED ON UKN/5000 FIBRE

As a result of the study, it was established that the most important factor determining the operational properties of products made of carbon-carbon composite materials (CCCM) is the adhesive interaction at the filler-binder interface, which depends on the adsorption capacity of carbon fibers (CF) and the wetting capacity of the matrix precursor (coal tar pitch). The properties of CF are determined by polyacrylonitrile (PAN) raw materials and manufacturing technology. The study examined the properties of carbon fibers obtained from various PAN raw materials and established a significant difference in structural characteristics (d002, ID/IG), as well as activation energy and specific surface area, which determine the difference in the defectiveness of the CF surface. Carbon rods based on these fibers with additional impregnation with a finishing composition based on polyvinyl alcohol (PVA) were manufactured and studied. A method for studying the wettability of carbon rods directly with coal tar pitch was developed. The dependence of the wettability of carbon rod samples with coal tar pitch in the temperature range from 60 to 150 °C was obtained. The change in pitch shape upon heating and viscosity reduction was recorded, characterizing the successive change in the physical state from elastic-viscous to viscous-flowing. The temperatures of the onset of wetting, the minimum contact angles of wetting of carbon rod samples based on carbon fibers of different manufacture were determined. The effective activation energy was calculated for different stages of wetting and impregnation, and assumptions were made about the kinetics of the processes in different temperature ranges. It was established that the finishing composition in the manufacture of carbon rods has a dominant effect on the functionality of the surface and, accordingly, the wettability of the matrix by the precursor and the adhesive interaction between the components of the composite. For citation: Sidorova E.V., Starichenko N.S., Karpov A.P., Fedushkina A.G., Bekheleva Yu.V., Yelchaninova V.A. Study of wettability of carbon rods based on UKN/5000 fibre. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2025. V. 68. N 9. P. 20-27. DOI: 10.6060/ivkkt.20256809.8y.