Mechanical and Tribological Properties of Glass Fiber/Polyethylene Hybrid Fiber Reinforced NBR Composites: Experiments and Molecular Dynamics Simulation

ABSTRACT To enhance the sealing efficacy of nitrile butadiene rubber (NBR) in oil conditions, the synergistic reinforcing effects of glass fiber (GF) and polyethylene fiber (PE) ratios on the mechanical and tribological properties of NBR composites were explored under normal, aging, and swelling conditions. The mechanical properties of NBR composites were first investigated under three different conditions. The results indicated that the composite with a GF/PE ratio of 7:3 shows the optimal effect, achieving a tensile strength of 22 MPa. After aging and swelling, the tensile strength of composites with this ratio was 21.2 and 20 MPa, respectively, showing a decrease of only 3.6% (aging) and 9.3% (swelling) compared to normal conditions. Then, the tribological properties of NBR composites under different conditions reveal that the composite with a GF/PE ratio of 7:3 also behaved the best tribological performance. Its coefficient of friction further decreased by 3.6% after aging and increased by 10.3% following swelling, compared to the normal condition. The wear surface of composites was experimentally examined to reveal the wear morphology and fiber debonding behavior. Overall, a GF/PE ratio of 7:3 in NBR composites provided optimal mechanical and tribological performance under three conditions. In addition, the synergistic enhancement mechanism of different GF/PE ratios in NBR composites was examined at an atomic level using molecular dynamics simulations. The findings of this work are expected to support the development of high‐performance and durable rubber sealing materials for the oil sealing industry.