A combination of experimental and theoretical approaches on SSBR/BR compounds reinforced by hybrid nano-silica/carbon black: Mechanical and rheological properties

In modern formulations for green tire treads, nano-silica combined with silane coupling agents has recently partially replaced carbon black (CB) to improve the well-known "magic triangle" of tire tread compounding. However, achieving adequate levels of CB in formulations is still a challenge. In this study, the effect of nano-silica/CB hybrid reinforcements and silane coupling agents on rubber compound prepared by melt blending method was investigated. Microstructure, swelling, mechanical and rheological properties of highly filled SSBR/BR-based compounds were investigated. The results showed that with the increase of CB content in SSBR/BR/TESPT/nano-silica, the properties pass an optimum point. Various properties were confirmed by field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM) images. Estimation of the properties of tire tread compounds is inevitable due to the high cost of the components and the time and energy savings. For this purpose, different theoretical models were used. The Bergstrom-Boyce, Ogden-Roxburgh and Mooney-Rivlin models were used to study the mechanical properties and the Herschel-Bulkley, Power law and Carreau-Yasuda theories were used for the rheological properties. Among the theoretical models used, the Bergstrom-Boyce model showed better correlation with the experimental data than other models.