Ethylene–propylene–diene rubber (EPDM) is used to manufacture various automotive parts and disposal of these parts is a problem. An industrial autoclave, an industrial twin screw extruder and a microwave apparatus with the aid of 2-mercaptobenzothiazoledisulfide (MBTS) and tetramethylthiuram disulfide (TMTD) devulcanizing agents and aromatic and paraffinic oils, were used to devulcanize the waste powder from discarded EPDM automotive parts. The devulcanized products formulated in a common formulation for the automotive rubber strips and then revulcanized with a semi-efficient (SEV) vulcanization system. The viscosity, cure and mechanical properties of the compounds were subsequently determined. This study showed that waste rubber was successfully devulcanized with the aid of chemicals and paraffinic and aromatic oils for all employed devulcanizing techniques. The oils had different effects on the devulcanization of the waste powder and MBTS was more efficient than TMTD. Therefore, a new effective recycling routes for the waste EPDM powder in the automotive rubber strips is now available.

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