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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.

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.

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.

Direct ink writing of soft materials is a very promising technology in 3D printing, and the rheological properties of inks are crucial for successful printing.In this paper, the effect of the rheological properties on the printing process of silicone rubber inks is studied to lay a foundation for the configurations of 3D printing process parameters. Also, the shape retention of the printing filaments is studied to provide a basis for the viscosity deployment of the inks. In addition, by studying the die swell ratio of nano-silica-reinforced silicone rubber inks at normal printing speed, it is found that the die-swell ratio is proportional to the ink's relaxation time. Finally, the influence of the configuration of the short-nozzle on the die swell is investigated, and the concave nozzle has a smaller extrusion swelling effect than the convex nozzle and the conical nozzle, providing new ideas for the adjustment of the filament diameter.