Effect of TESPT on viscoelastic and mechanical properties with the morphology of SSBR/BR hybrid nanocomposites

Abstract

AbstractIn this study, the various properties of hybrid nanocomposite based on solution styrene butadiene rubber (SSBR)/butadiene rubber (BR) have been investigated. For this purpose, SSBR/BR rubber blend with nano‐silica and carbon black (CB) in constant filler content (60 phr) with and without Bis (triethoxysilylpropyl) tetrasulfide (TESPT) silane coupling agent was fabricated. The various properties, including curing behavior, morphology, dynamic–mechanical, and dissipation characteristics, were studied. For this objective, rheometry, field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM), tensile test, and Dynamic mechanical thermal analysis (DMTA) were used. The results of rheometry illustrated that the addition of nano‐silica increased the optimum cure time (t90) and declined the cure rate index (CRI). However, the addition of surface‐modified silica improved the t90 and CRI. Replacing nano‐silica with CB also reduced the scorch and optimum cure time. TEM and SEM micrographs showed the good dispersion state of nano‐silica in the SSBR/BR/nano‐silica/TESPT matrix. According to the mechanical test data, including tensile, hardness, and abrasion, the addition of hybrid filler containing 40 phr modified nano‐silica and 20 phr CB improved properties. The results of DMTA illustrated the appropriate compatibility between blend phases, also an increase in the glass transition temperature (Tg) and storage modulus (E′) for the samples containing higher amounts of CB. Considering the importance of the damping factor at temperatures of −20, 0, and 60°C, which is related to ice grip, wet grip, and rolling resistance, respectively, the TSi40CB20 sample showed the essential properties of the magic triangle better than other samples. Dissipative properties also revealed that by increasing the filler content and replacing nano‐silica with CB, the dissipation of the compound increases significantly. According to the results, the optimum amount of nano‐silica and CB in the SSBR/BR/TESPT was 40 and 20 phr, respectively.