The role of various modifiers in the compatibilisation of PP/PET blends – rheological
and structural properties (in English)
Polimery 2004, No 11-12, 819
The present paper deals with structural and flow properties of polypropylene (PP) and poly(ethylene terephthalate) (PET) blends compatibilized by maleic anhydride (MA) in combination with two modifiers - epoxidized thermoplastic elastomer and silicone/acrylic-based rubber. Rheological experiments were performed at both steady and dynamic (oscillating) shear regimes at temperature 245°C and 265°C, i.e. below (when PET particles are not completely molten acting as soft filler) and above melting temperature of PET. Increased rheological functions are generally observed for PP/PET/MA (due to enhanced interfacial interactions), which is further improved by elastomeric modifiers. These also bring satisfactory phase structure resulting from possible reactions between functional groups of the modifier and blend components, particularly for epoxy-modified thermoplastic elastomer. From the application viewpoint, the addition of elastomeric modifiers leads to a significant increase in viscosity of PP/PET blends, which can be useful in their processing, for example in extrusion of mixed plastics wastes.
Keywords: polypropylene, poly(ethylene terephthalate), blends, elastomeric compatibilizer, rheological properties, structure
The role of various modifiers in the compatibilisation of PP/PET blends - rheological and structural properties (in English)