Transforming vulcanized styrene–butadiene waste into valuable raw material: an opportunity for high-impact polypropylene production

Polypropylene (PP) compounds with styrene–butadiene rubber residue (SBRr) from the footwear industry were produced, adding styrene-(ethylene–butylene)-styrene (SEBS) as a compatibilizer, 20% and 30% of styrene (St.). The PP/SBRr PP/SBRr/SEBS processed in co-rotating twin-screw extruder injection molded. addition SBRr did not compromise processability, torque melt flow index increased slightly compared to neat PP. Significant increases impact strength achieved for (10–20% St.) (10–30% St.), gains 316% 248% related elastic modulus, tensile strength, elongation at break, Shore D hardness indicated greater flexibility PP/SBRr/SEBS, especially copolymer St. When system was made compatible SEBS (30% relation (20% St.). Such behavior suggested that more effective increasing resistance deformation compounds, heat deflection temperature (HDT) even high content PP, HDT severely affected, possibly due its crosslinked character. compatibilization inhibited PP crystalline peaks, verified through X-ray diffraction (XRD). Stable morphology upon 10% PP/SBRr, providing proper interfacial adhesion fine particles, contributing toughening Acquired results are promising recycling, aiming produce high-impact polypropylene containers furniture accessories applications.