Compatibilization of PET/PS blends through SMA and PMPI dual compatibilizers

Tn this study, dual compatibilizers composed of styrene maleic anhydride ra ndom copolymer (SMA-8 wt.% MA) and poly[methylene (phenylene isocyanate)] ( PMPI) have demonstrated to effectively compatibilize the immiscible and inc ompatible blends of poly(ethylene terephthalate) (PET) and polystyrene (PS) . SMA with low MA content is totally miscible with PS to make the PS phase quasi-functionalized, so that PMPI has the chance to contact and react with PET and SMA simultaneously to form PET-co-PMPI-co-SMA copolymers at the in terface. These desired copolymers are able to anchor along the interface an d serve as efficient compatibilizers. The compatibilized blends, depending on the quantity of dual compatibilizers employed, exhibit higher viscosity, finer phase domain, and improved mechanical properties. Moreover, the crys tallization behavior of the PET component in these compatibilized blends ha s been affected. (C) 1999 Elsevier Science Ltd. All rights reserved.