Thermoplastic elastomers based on polypropylene/natural rubber and polypropylene/recycle rubber blends

Fine rubber powder obtained from the sanding process of polishing rubber balls and artificial eggs (recycled rubber, RR) was used to prepare polypropylene (PP)/RR blends, a thermoplastic elastomer using different RR content. A similar series of blends using natural rubber, SMR L (NR) was also prepared. The results indicated that at a similar rubber content, PP/RR blends have higher, tensile strength and Young's modulus but lower elongation at break and stabilization torque than PP/NR blends. Scanning electron microscopy (SEM) examination of the tensile fracture surface of PP/RR blends indicates that a higher energy is needed to cause catastrophic failure compared to PP/NR blends. (C) 2002 Elsevier Science Ltd. All rights reserved.