Optimization of mechanical and thermal properties of hybrid styrene‐butadiene rubber/nanoclay/graphite nanocomposites

Abstract

In this study, solid styrene‐butadiene rubber (SBR) compound nanocomposites containing hybrid nanoclay–graphite nanofillers with different weight fractions were fabricated through a two‐roll mill process, and surface response methodology (SRM) using Minitab software was employed for designing experiments and developing good relationships between independent factors and responses. The impact of nanoclay, graphite, and their hybrids on the mechanical, aging, and thermal properties of filled SBR was studied. Compared with neat SBR, the SBR containing 10 phr nanoclay and 15 phr graphite (SBR/10/15) showed the highest tensile strength and tensile modulus with 55 and 47% rise, respectively. Also, A maximum increase in hardness was observed for SBR/5/30 by 42%, and it was revealed that nanofillers reduced the elongation at break. Additionally, despite reducing the mechanical properties of neat SBR, hybrid nanocomposites maintained their properties during aging so that the SBR/10/15 presented maximum aging resistance. The SBR/10/15 presented maximum aging resistance as it significantly retained its mechanical properties during the test. Moreover, thermal stability was investigated using thermogravimetric analysis (TGA). The results demonstrated that the hybrid nanofillers improved the thermal stability of SBR.