Determination of optimum De-Link R concentration in a recycled rubber compound

This study attempts to determine the most desirable quantity of De-Link R suitable for recycling the rubber powder generated in large quantities as a waste product of manufacturing rubber balls and artificial eggs. Attempts were also made to assess the extent to which the devulcanization system scissions the crosslinks in the rubber vulcanizate by means of solubility test. Monsanto moving die rheometer (MDR 2000) was used to determine the rheological properties and cure characteristics of the recycled compound (DE-VULC). The tensile properties of the vulcanizates were correlated with the results from MDR 2000. The behaviour pattern of torque maximum, torque difference, cure time and tensile properties indicated that 6 phr is the optimum concentration of De-Link R. The resulting DE-VULC is not fully devulcanized as it dissolves only to a limited extent in a suitable solvent.