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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, Tg = −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 results of an experimental study of the effect of the normal pressure in the range of 0.1-0.3 MPa, a velocity of sliding of 1-100 mm/s, and a bulk temperature of 22 to -27°C on the coefficient of sliding friction of an elastomer-steel friction pair have been presented. Two types of elastomeric materials have been considered, i.e., frost resistant rubber based on synthetic propylene oxide rubber and this rubber filled with the antifriction additive of ultrafine polytetrafluoroethylene powder in an amount of 1 weight part per 100 weight parts. The results have shown the efficiency of filling rubbers with ultrafine polytetrafluoroet hylene; the coefficient of sliding friction at temperatures below -15°C decreases by more than two times.

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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.