<p>This study examines the influence of accelerated weathering on the mechanical properties of grafted binary blend (Room Temperature Vulcanized Silicone Rubber (RTV-SIR)/polyurethane Rubber (PUR) intended for prosthetic feet. Employing an accelerated weathering environment replicating natural conditions, encompassing UV radiation, condensation, and water spray, the samples produced by the vacuum desiccator were exposed for a duration of 100 h. Grafted binary blend samples of (PUR) with (10, 20, and 30 wt.% RTV-SIR) blended to achieve different properties to use for prosthetic foot, using 0.1% of Tetraethoxysilane (TEOS) as a coupling agent to enhance compatibility between components. To compare, mechanical tests characterised tensile, tear, compression, and hardness properties of weathered and unweather samples. Fourier-transform infrared spectroscopy (FTIR) also analysed the efficiency of the TEOS treatment of binary rubber blend samples. Field emission-scanning electron microscopy (FE-SEM) was employed to investigate the morphology and interfacial adhesion between the components. The findings illustrate increased mechanical properties with weathering exposure, and FESEM showed better interfacial adhesion between blend components for (10–20 wt. % RTV-SIR). This work proves that the binary rubber blend was more resistant to accelerated weathering than its components and is compatible with a weight ratio of less than 30% of RTV-SIR.</p> Graphical Abstract <p></p>