To investigate the effect of molybdenum disulfide (MoS2) on the mechanical and tribological properties of nitrile butadiene rubber (NBR) composites under high-temperature cyclohexane (C6H12) swelling,Monte Carlo method and Forcite module were used to establish models for Pure NBR,swollen NBR,NBR/MoS2,and swollen NBR/MoS2,respectively.The effect of MoS2 on the high-temperature swelling,mechanical and tribological properties of NBR was studied,and the mechanism of MoS2 improving the high-temperature swelling of NBR was explored.The results show that the C6H12 swelling leads to the decrease of mechanical properties of NBR,but after adding MoS2,the mechanical properties of the composite material are improved.The molecular chain migration and movement rate inside NBR are accelerated by C6H12 swelling,but the addition of MoS2 effectively inhibits the C6H12 swelling.The C6H12 swelling can increase the surface molecular chains of NBR composite materials,leading to the decrease of tribological properties of NBR.However,the addition of MoS2 improves the tribological properties of the composite materials.Due to the larger specific surface area of MoS2 and the stronger van der Waals forces and electrostatic force adsorption,the addition of MoS2 can improve the mechanical and tribological properties of the NBR composites under high-temperature C6H12 swelling.