The physical and mechanical properties of nitrile–butadiene rubber (NBR) composites with N-cetylpyridinium bromide-carbon black (CPB-CB) were investigated. Addition of 5 parts per hundred rubber (phr) of CPB-CB into NBR improved the tensile strength by 124%, vulcanization rate by 41%, shore hardness by 15%, and decreased the volumetric wear by 7% compared to those of the base rubber-CB composite.

Frost-resistant rubbers retain their highly elastic properties over a wide temperature range. They are used in various friction units (e.g., seals), but their high friction coefficient and low wear resistance lead to the need for frequent replacement. In this paper, we propose applying thin (several hundred microns) UHMWPE coatings to formed rubber rings. The application technology depends on the required coating thickness. Friction tests of the coatings and pure UHMWPE were performed using the ball-on-disk (unidirectional sliding) scheme for various loads and velocities. In the experiments, the friction coefficients and temperatures near the contact area were determined. Friction tracks were studied using microscopy methods. The sliding contact of the ball and the two-layer material was modeled to obtain the dependences of the deformation component of friction on the sliding velocity for coatings of different thicknesses. UHMWPE is sensitive to frictional heating, so the thermal problem of determining the temperature in the contact area was also solved. It is shown that the minimum friction coefficient occurs for coatings with a thickness of 600 μm. At the same time, in the case of the 300 μm coating, the surface of the friction track is practically no different from the initial one. Thus, the studied combination of polymers provides antifrictional properties and wear resistance to the surface layer while maintaining the damping properties of rubber.

Sealing rubbers employed in cold climates such as the Siberian Arctic must be able to withstand temperatures as low as −50 °C while still exhibiting specific relaxation, strength, tribological characteristics, and a resistance to aggressive media. Previous investigations of propylene oxide rubber (SKPO, T_g = −73 °C) modified with polytetrafluoroethylene (PTFE) have revealed that, while the rubber composite materials exhibit double the wear resistance compared to unmodified polypropylene oxide rubber, they have poor frost resistance. In the present study, we developed materials based on SKPO and ultrafine PTFE (UPTFE), which can be characterized by its smaller particle size, low molecular weight, high tribo-technical characteristics, and resistance to aggressive media. The properties of the rubber composites were evaluated using the standard methods. The structures of the materials were investigated by electron microscopy and XRD analysis. It was shown that the materials have excellent wear resistance, resistance to aggressive media, compression set, and low-temperature resistance. The addition of UPTFE is preferable to the addition of PTFE because the desired positive effects can be attained with only 0.5–1 parts per hundred parts of rubber (phr) UPTFE while 20 phr PTFE would be necessary.

The operability of frost-resistant industrial sealing rubbers on the basis of full-scale exposure of rubber samples in the environment of oil in cold climate has been investigated. It is found that interaction of rubbers with oil media (fuel, lubricants) causes diffusion of a plasticizer from the elastomer material into the contacting medium and decrease of frost resistance coefficient. Choosing the material for production of different seals for the conditions of the North one must use rubbers with significant temperature range of operation, for example propylen-oxide elastomer, which is highly frost resistant and has a stable set of operational properties.