Comparison of structure and properties of two styrene-butadiene rubbers filled with carbon black, carbon-silica dual-phase filler, and silica

Heat buildup, wet skid resistance (WSR), wear resistance (WR), and cutting and chipping resistance (CCR) of carbon black (CB), carbon-silica dual-phase filler (CSDPF), and silica-filled two kinds of styrene-butadiene rubber (SBR) were investigated. For the same SBR systems, the composite filled with silica exhibited the lowest heat generation and highest WSR performance, whereas it showed the worst WR and CCR among the three composites. The CSDPF-filled composite obtained a balanced overall performance. Rubber processing analyzer (RPA) strain sweep results showed that the CSDPFfilled composite exhibits the lowest Payne effect, which is related to filler networking in the rubber matrix. Solid-state 1HlowfieldNMRdemonstrated that the sequence of the filler-rubber interaction of the composites was CB>CSDPF>silica. Bis-(3-(triethoxysilyl) -propyl)-tetrasulfide increased the cross-link density of the silica-filled composite. For the composites with different fillers, the lower filler network structure and higher cross-link density result in the lowest heat generation of silicafilled composite, and the strongest filler-rubber interaction leads to the best WR and CCR performances of the CB-filled composite. Filled SBR5025 composites exhibited better WR, lower heat buildup, and worse CCR than filled SBR1712 composites with the same filler.