The effects of crosslinking densities on mechanical properties of nitrile rubber (NBR) composites before and after thermal oxidative aging are investigated. Tensile strengths of NBR composites are enhanced slightly at the initial aging stage, attributing to moderate increment of crosslinking densities. Continuous decrease with further aging is followed, resulting from over‐crosslinking and uneven distribution of crosslinking densities. The digital image correlation method is explored for large‐strain deformation measurement by displacement accumulation and establishing strain model, being promising in practical age detection and measurement of mechanical properties in complex environments. Compression sets are gradually increased with aging because of the destruction of the original crosslinking structures. The molecular chains fracture inhibits elastic recoveries of compressive NBR composites and results in residual deformation in thermo‐oxidative and compressive environment after unloading. This study provides new ideas for exploring mechanical properties of rubber‐based composites before and after thermal oxidative aging.

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The dry/wet environment's effects on the sliding friction properties of fabric–silicone rubber composites are studied, and the wear resistance of polyester fabric is evaluated. The yarn directions of the fabrics (inner and outer) have significant influence on the coefficient of friction (COF) of fabric–silicone rubber composites during sliding friction due to the difference in fabric texture and yarn modulus. The COF's variation laws of fabric–silicone rubber composites under different vertical loads and sliding rates are observed, respectively. Additionally, the outer fabric is more sensitive to the changes of vertical loads than those of the sliding rates under the wet environment, which can be attributed to the destruction of the fabric original structure by high load, resulting in the fabric fibers' pulling and breaking during the steel ball's sliding. This study provides new ideas for the design of fabric–silicone rubber composites applied in friction conditions and complex environments.

The effects of titanate on the mechanical properties of silicone rubber and peel strength of polyester fabric with silicone rubber are studied. The tests show that the hardness and mechanical properties of silicone rubber containing 0.2 phr titanate are similar to those of pure silicone rubber, and the peel strength (1.11 N/mm) between fabric and rubber matrix without inner fabric is the highest in the test groups. Fourier transform infrared spectra (FT-IR) and contact angle test indicate that the surface wettability of silicone rubber is effectively enhanced with the addition of titanate, which is a key factor to improve the bonding properties between silicone rubber and polyester fabric because of the more adequate contact between the adhesive and silicone rubber surface.Due to the difference in the modulus of the fabric along different yarn directions, the peel direction has a significant effect on the peel force between the outer fabric and silicone rubber.

In this work, low density hollow glass beads (HGB)/silicon rubber (SR) composites were prepared by solution method and flocculation process. The prepared samples were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, tensile test, and friction test. The results show that the densities of SR composites decrease from 1.140 to 0.792 g/cm3 with the addition of HGB. By comparing theoretical density with true density, it can be estimated that the ratio of shattered HGB increase from 8.79% to 24.76%. Especially, the mechanical properties of SR composites were improved by surface modification of HGB. By adding surface‐modified HGB at 5 and 10 wt%, the tensile strengths of SR composites were enhanced by 17.8% and 28.2%, respectively. In addition, tear strength, shore A hardness, compression set, and friction property were significantly ameliorated. Furthermore, the mechanism of surface‐modified HGB in mechanical properties was analyzed.