Influence of graphene/ferriferrous oxide hybrid particles on the properties of nitrile rubber

Abstract

The reinforcement of rubber by graphene has generated great interest in recent years. The dispersion of graphene in a rubber matrix, however, remains a challenge. In this study, ferroferric oxide (Fe₃O₄) was used as a carrier to prepare graphene/Fe₃O₄ hybrid particles, in order to improve the dispersion of graphene in nitrile rubber (NBR). The graphene hybrid particles prepared by co-precipitation synthesis was added into NBR solution to prepare composites. Results show that there was about 90% improvement in tensile strength when 4 phr of graphene hybrid particles (equally only 0.5 phr of graphene in NBR) were added to the matrix. In contrast, the tensile strength of NBR decreased when 4 phr of Fe₃O₄ were added. SEM and XRD both explained the mechanism for the reinforcement of graphene hybrid particles. The DMA results show higher T_g and a higher value of tan δ for the modified NBR, further proving the reinforcement mechanism, i.e. the hybridization of graphene and Fe₃O₄ improves the dispersion of graphene in NBR and the interfacial action of graphene with NBR. Moreover, addition of graphene hybrid particles gives NBR extra properties such as surface wettability and magnetism, providing a useful guide for the preparation of functional graphene/rubber composites.