Synergistic reinforcement of styrene–butadiene rubber with a hybrid graphene/helical carbon nanofibers network at low loading

A novel strategy is proposed to enhance the performance of styrene–butadiene rubber (SBR) by constructing a hybrid filler network comprising graphene (GE) and helical carbon nanofibers (HCNFs). In this study, SiO 2 /GE/HCNFs/SBR composites were prepared via a two-step “wet masterbatch-dry blending” process. The results demonstrate that GE and HCNFs exhibit complementary effects in geometric morphology and mechanical properties. Optimal comprehensive performance was achieved at a GE:HCNFs mass ratio of 1:2 (total filler loading of 2 phr). Compared with the pure SiO 2 compound, the tensile strength increased by 30.6 %, tear strength improved by 29.4 %, abrasion loss volume decreased by 25.9 %, and the elongation at break remained above 530 %. At this optimal ratio, the loss factor (tan δ ) at 60 °C decreased by 10.8 %, whereas no significant reduction was observed at 0 °C, thereby achieving an excellent balance between low rolling resistance and wet traction. Quantitative analysis revealed that the synergistic contribution of HCNFs and GE reached as high as 53.5 %. This study achieved efficient reinforcement of SBR at ultra-low filler loadings through a rationally designed GE/HCNFs hybrid system, offering an innovative approach to breaking through the “Magic Triangle” bottleneck in tire materials.