The effect of ground tire rubber modified by deep eutectic solvents on the viscoelasticity of silica‐filled styrene‐butadiene rubber

Abstract With the development of the recycling economy for waste rubber, the high‐value application of rubber powder, such as the modifier in asphalt mixture and the polyurethane foam, has attracted more and more attention. In the study, the surface characteristics of rubber powder modified by deep eutectic solvents were investigated by infrared spectroscopy, sol fraction, solid surface energy, and scanning electron microscope. The mechanical properties of modified ground tire rubber powder (M‐GTR)/SBR/silica composites were studied. Meanwhile, the viscoelasticity of the composites was characterized by the Payne effect and Mullins effect. Compared with the unmodified rubber powder, the rubber powder treated at 105°C had a higher sol fraction and maximum value of solid surface energy. With the increase of the content of M‐GTR, the Payne effect of the M‐GTR/SBR/silica composites firstly weakened and then increased. As for the Mullins effect, the vulcanizates showed stress‐softening phenomenon in the process of uniaxial cyclic compression. The recovery ability of the Mullins effect strongly depended on temperature. Besides, the modified rubber powder could improve the dispersity of silica in the SBR matrix, and the Mullins effect of the composite contained modified rubber powder was weak, which would provide potential high‐value application for rubber powder.