Blends of poly(ethylene terephthalate) bottle waste with modified styrene butadiene rubber through reactive mixing

Abstract

Styrene butadiene rubber (SBR) was modified by the grafting reaction of maleic anhydride (MAH) in the presence of the initiator benzoyl peroxide (BPO). This modified elastomer was then blended with poly(ethylene terephthalate) (PET) bottle waste, and the mechanical and morphological properties of the resulting blends were studied. The amount of grafted MAH was determined by chemical titration. The results revealed that the concentrations of MAH and BPO strongly affected the grafting process. The morphology of the dispersed phase for blends of PET waste and SBR-g-MAH was quite different from that of a simple blend of PET waste and SBR. Dynamic mechanical thermal analysis revealed suitable compatibility between PET waste and styrene butadiene rubber-graft-maleic anhydride (SBR-g-MAH). The enhanced compatibility resulted in better impact properties. The better compatibility was concluded to result from bond formation between the carbonyl group of SBR-g-MAH and the hydroxyl or carboxyl end groups of PET. © 2006 Wiley Periodicals, Inc.