▎ 摘 要
The present work discusses the effects of reduced graphene oxide (rGO) on the nonlinear viscoelastic behavior, or the Payne effect, of silica/styrene-butadiene rubber compounds. The volume fraction of unmodified silica was constant, while the amount of rGO in these hybrid filler compounds varied. Dynamic-mechanical analysis (DMA) in strain sweep mode showed that adding a small quantity of rGO to the silica-filled compounds resulted in diminished network formation of unmodified silica as well as a reduced Payne effect and corresponding energy dissipation. The state of silica dispersion in the presence of rGO in the rubber matrix was predicted by calculating the work of adhesion in a three-component system and detected by scanning electron microscopy. It was observed that the dispersion of the unmodified silica was improved by the addition of only 0.25 or 0.5 phr rGO, which may be due to the improved silica-rubber interactions that occur during mixing and/or reduced silica flocculation after mixing, as measured by DMA in time sweep mode. The synergy between silica and small quantities of rGO (0.25 or 0.5 phr) resulted in an enhancement in mechanical strength (45%) and abrasion resistance (63%), as well as a reduction in heat build-up (23%). This hybrid system can be considered an alternative to silane modification of silica in green tire technology.