Effects of composition and dynamic vulcanization on the rheological properties of PP/NBR blends

Rheological behavior of isotactic polypropylene (PP) and nitrile rubber (NBR) blends, in the composition range of 10-30-wt % NBR content were studied, with special reference to the effect of blend ratio, dynamic vulcanization and compatibilization. All blends were prepared in a twin-screw extruder. Capillary Rheometry was employed. Pseudoplastic behavior of blends was favored by increasing rubber content. The incorporation of NBR into PP lowered activation energies. Compatibilization of unvulcanized blends did not produce significant changes on flow behavior. Dynamically vulcanized blends provide unique processing characteristics that enable to perform well in both injection molding and extrusion.