Effect of pulverized coal/carbon black hybrid fillers on mechanical properties and thermal stability of styrene butadiene rubber composites

Abstract

Pulverized coal (coal) possesses a layered structure similar to graphite and is a potential reinforcing filler. In this paper, ball milling is used to reduce the particle diameter of coal. The coal is modified with KH‐560 to obtain K‐COAL and prepared K‐COAL/styrene‐butadiene rubber (SBR) composites. In addition, carbon black (CB) is modified to obtain CB‐Si69, K‐COAL and CB‐Si69 are added to SBR in different ratios to prepare COAL/CB/SBR composites. The results show that the addition of K‐COAL can improve the vulcanization performance, thermal stability, and mechanical properties of SBR composites, but the reinforcing effect is weak. In the COAL/CB/SBR composites, the vulcanization and mechanical properties of the composites gradually increase with the increase of CB, while those of the thermal stability decrease. The tensile strength of the 10 phr COAL/30 phr CB/SBR composite is 24.1 MPa, which is elevated by 1105% and 205% compared with the pure SBR and 40 phr K‐COAL/SBR composites, respectively. The composites maintain high elasticity while the tensile strengths are greatly improved, and the mechanical properties are significantly enhanced. In conclusion, this paper provides a reference for the clean utilization of coal and shows new possibilities for finding new fillers to replace CB.