Graphene/carbon black/natural rubber composites prepared by a wet compounding and latex mixing process

The extensively used latex mixing approach to prepare graphene can improve the graphene dispersion but meets some challenges in the preparation of high content carbon black filled rubber system like a rubber tire. Owing to the high melt viscosity of the rubber/graphene masterbatch, the dispersion of carbon black is not perfect during twin-roll mixing and some aggregates will be formed. Here we proposed a wet compounding process, combined with ultrasonically assisted latex mixing, named as the WCL method to prepare reduced graphene oxide/carbon black/natural rubber (rGO/CB/NR) composites. The morphological observations confirmed that both graphene and carbon black can be evenly dispersed in the rubber composites. The incorporation of rGO also improves the hardness, thermal conductivity and anti-aging properties of the composites. The rGO/CB/NR composites prepared by the WCL method possess better mechanical properties compared to conventional latex mixing. The entanglement-bound rubber tube model was utilised to understand the reinforcing mechanism.