ИСТИНА

The effect of multi-walled carbon nanotubes (CNT) on the tribological and mechanical properties of sealing rubbers developed for use in the cold Arctic climate was experimentally studied. Two types of frost-resistant rubber based on epichlorohydrin (EPCHG) and butadiene-acrylonitrile (BNKS) rubbers were selected as objects. Rubber nanocomposites were prepared by mixing CNT with rubber in plasticorder Brabender and then vulcanizing in a mold. CNT were functionalized by oxygen. The static and dynamic coefficients of sliding friction were determined on a tribometer according to the contact scheme rubber ring – steel disc (simulation of the end seal) at two values of volume temperature T: 23 and –25 °C in the range of normal pressures (P) 0,1 – 0,4 MPa and sliding velocity V = 0,1–100 mm/s. Comparative tests to assess the abrasive wear resistance of the obtained nanocomposites were carried out at P = 0,4 MPa, V = 10 mm/s, and T = 23 °C. In this work it was demonstrated that the reinforcement of the studied rubber CNT does not change the static friction coefficient for EPCHG rubber. Dynamic friction coefficient in the range of sliding velocity of 0.01…0.1 m/s increases with growth of CNT concentration in rubber. The results of the wear resistance assessment showed that the incorporation of CNT in small concentrations (1...5 wt%) increases doubly the wear resistance of studied EPCHG rubbers while maintaining their elasticity. Meanwhile the wear resistance of samples of BNKS rubber was increased only slightly. The study was supported by the RFBR Grant No 19-08-00615.