Abstract: A method, and product thereof, for modifying the surface of recycled sulfur-cured rubber via surface devulcanization that minimizes alteration of the network structure of the recycled sulfur-cured rubber, while generating strong tack between mixed recycled rubber and fresh rubber for optimal adhesion upon subsequent co-curing. In one embodiment, the surface of recycled rubber is devulcanized by treating recycled rubber with a thiol and a base dissolved in a solvent that does not effectively penetrate and only minimally swells vulcanized rubbers.

Abstract: A method of recycling rubber includes pre-treating vulcanized ground rubber to prevent the vulcanized ground rubber from encountering significant additional crosslinking during co-vulcanization with fresh rubber compound, and promoting better bonding between the vulcanized ground rubber and the fresh rubber compound. The ground vulcanized rubber can be coated with a layer of non-vulcanized rubber that includes cure inhibitors or other ingredients dispersed within the layer to aid in the coating process and/or co-vulcanization of the vulcanized ground rubber and fresh rubber compound. The vulcanized ground rubber can also be pre-treated with a mixture of at least one chemical curing agent inhibitor and a solvent capable of solubilizing the chemical curing agent inhibitor and dispersing the curing agent inhibitor within the vulcanized ground rubber.

Abstract: A method for microbial and/or enzymatic devulcanization of rubber includes: providing a particulate vulcanized rubber compound, swelling the vulcanized rubber compound in a solvent, and introducing a microbe or enzyme into the solvent containing the particulate vulcanized rubber in order to devulcanize the rubber compound.