Enhanced carbon black exfoliation through elongational flows for faster and higher value-added rubber recycling

Abstract

The recycling of rubber featuring intricate three-dimensional crosslinked networks necessitates the application of cutting-edge technology and specialized machinery. In this study, the rubber was recycled by mechanochemistry under elongational flow field. The crosslink bonds in the rubber were rapidly broken through the high extension of molecular chains, without the need for additives or additional refinements. At 200 °C, the waste rubber is devulcanized in only 2 min so that the sol molecular weight reached an impressive 3.3 × 104 g/mol, and the mechanical properties of the reclaimed rubber were significantly enhanced, reaching a tensile strength of 17.44 MPa. The elongational flow field devulcanizes the waste rubber while simultaneously achieving rapid refinement of rubber particles and exfoliating the carbon black from the crosslinked network. These making reclaimed rubber forms a micro-nano microstructure in natural rubber (NR), which makes particle reinforcement of the NR-matrix. Faster and high-value-added rubber recycling achieved successfully through elongational flows.