Dispersing carbon dots in non-polar rubber by slurry compounding and in situ compatibilizing

Carbon dots (CDs) have gained increasing attention in the elastomer composites due to their unique physical and chemical properties. Nevertheless, due to high hydrophilicity of most kinds of CDs, it is difficult to achieve a fine CDs dispersion within the non-polar rubbers by traditional melt milling, especially when the CDs loading is high. To tackle this problem, we propose a simple and cost-effective strategy, i.e., the combination of slurry compounding and in-situ compatibilizing, to prepare the rubber/CDs composites. The CDs slurry was simply prepared by mixing the CDs powder with water. Subsequently, the slurry along with the compatibilizer (polybutadiene grafted with maleic anhydride, BR-g-MAH) were compounded with rubber via open milling. The resulted rubber composites exhibited significantly improved mechanical properties. More importantly, the CDs endowed the rubber with exceptional antioxidative property. We envisage that this scalable yet environmentally-friendly strategy may pave the way for industrial-scale utilization of CDs in the elastomer and beyond.