In situ fabrication of graphene oxide supported nano silica for the preparation of rubber composites with high mechanical strength and thermal conductivity

Abstract

Graphene oxide (GO) supported nano silica (SiO2), SiO2‐GO, was synthesized via in situ hydrolysis and condensation of tetraethylorthosilicate (TEOS) on GO surface. It was proved that SiO2 nanoparticles with an average particle diameter of ca. 30 nm were covalently grafted through Si—O—C bonds and evenly distributed on the surface of GO sheets. Subsequently, SiO2—GO was incorporated into styrene‐butadiene rubber (SBR) latex to prepare elastomer composite (SBR/SiO2‐GO). As expected, because of the unique architecture of SiO2‐GO, the irreversible agglomeration of SiO2 or GO was eliminated and the nanohybrid was uniformly dispersed in the rubber composites. In addition, the interfacial interaction between SiO2‐GO and rubber was also significantly improved. Consequently, SBR/SiO2‐GO composites showed much higher mechanical strength than SBR composites containing equal amount of GO or physical mixture of SiO2/GO. For example, when the filler content is 6 phr, the tensile strength of SBR/SiO2‐GO composites is further increased by 21% and 94% compared to those of SBR/GO and SBR/SiO2/GO composites, respectively. Moreover, SiO2‐GO nano hybrid can also endow rubber composites with better thermal conductivity than the physical mixture of SiO2 and GO. Potentially, this unique hybrid architecture synthesized in this work may provide a new method for the preparation of high‐performance elastomer composites. POLYM. COMPOS., 40:E1633–E1641, 2019. © 2018 Society of Plastics Engineers