Study on the effect of particle size and dispersion of SiO2 on tribological properties of nitrile rubber

Background: The friction and wear of water-lubricated bearings has always been an engineering problem that we need to solve urgently. Object: To investigate the influence of SiO2 particle size and dispersion on the friction and wear properties of nitrile rubber. Method: The friction and wear performance of rubber compounds (SiO2 ((nano))/NBR, SiO2 ((micr))/NBR and SiO2 (TEsp)/NBR) was tested by American Rtec multifunctional friction and wear test machine under the conditions of water lubrication and constant temperature. Results: The results showed that the particle size of SiO2 has a great impact on its dispersion in nitrile rubber, and the surface modification of SiO2 can significantly improve its dispersion. SiO2 ((TESPT))/NBR showed a good friction coefficient under low-speed and high-load conditions. The wear of SiO2 ((nano))/NBR and SiO2 ((micr))/NBR, which was mainly the fatigue wear, was relatively serious. In contrast, the modified SiO2 had a smaller particle size, better dispersion and stronger interfacial bonding with the nitrile rubber matrix. This significantly reduced the wear of SiO2 ((TESPT))/NBR, which was mainly the abrasive wear, and improved its wear resistance.