Compatibilizing effect of poly(butylene terephthalate)-g-polystyrene synthesized from macromonomer

Dihydroxy-terminated polystyrene (PS) macromonomers of various molecular weights were prepared by free-radical polymerization of styrene in the presence of a chain transfer agent, 3-mercapto-l, 2-propanediol. These macromonomers were used for the synthesis of poly(butylene terephthalate) (PBT) grafted with PS (PBT-g-PS). The morphology and glass transition behavior showed the compatibilizing effect of PBT-g-PS in PBT-PS blends. The compatibilizing effect was generally increased up to 10 phr of PBT-g-PS, and some adverse effects were observed above 10 phr.