Silicon dioxide nanoparticle decorated graphene with excellent dispersibility in natural rubber composites via physical mixing for application in green tires

The low dispersion of graphene is the main obstacle restricting the application of graphene in the natural rubber (NR) composites, especially in the green tire field. The present study addresses this important issue by developing a new hybrid filler, which is made from silicon dioxide nanoparticles (NSi) decorated reduced graphene oxide (rGO), denoted as GSi. Not only can the GSi filler be directly added to NR via mechanical mixing, but also excellent rGO dispersion is obtained, which greatly enhances the properties of the composites. The properties of GSi/NR composites are compared with those obtained by directly mixing equivalent concentrations of NSi and rGO (rGO/NSi/NR composites). The heat build-up and Akron abrasion loss of GSi/NR composites are only 18.4 °C and 0.149 cm3, 10.3% and 18.8% lower than the rGO/NSi/NR composites. Moreover, the tensile strength, elongation at break and heat resistance index of GSi/NR are up to 27.5 MPa, 507% and 182.2 °C, respectively. Besides, the abrasion loss and tensile strength can be further to 0.114 cm3 and 30.7 MPa by regulating the dosage of graphene oxide in the preparation of GSi. These results demonstrate that the GSi hybrid filler has high application value for the industrial-scale manufacture of green tires.