Effect of Reprocessing Cycles on the Morphology and Mechanical Properties of a Poly(Propylene)/Poly(Hydroxybutyrate) Blend and its Nanocomposite

The use of polymer blends and composites based on fossil-based bio-based polymers has become an important environmentally protective alternative for common disposable plastics applications such as packaging, bottles trays. disposal these more degradable products, however, may also harm the environment and, therefore, recycling systems becomes relevant. Recycling involves reprocessing which can significantly change morphology properties polymeric products. Therefore, this study deals with effects cycles nanocomposites fossil polymers. investigated were: a) neat polypropylene (PP), b) a polypropylene/poly(3-hydroxybutyrate) (PP/PHB) blend c) PP/PHB/organoclay nanocomposite compatibilized polypropylene-g-maleic anhydride (PP-g-MA) erucamide. These materials were submitted to up seven extrusion in single screw extruder operating at 60 rpm. Samples taken after first, third, fifth seventh their tensile determined. Scanning electron microscopy indicated that two phases observed showed spherical PHB domains. addition clay, PP-g-MA erucamide improved adhesion between components. X-ray diffraction analysis crystallinity tended increase number all cycle then decrease. A 10% was PP cycle. In general, decreased highest losses PP/PHB processing 50% 37% decreases stress break elastic modulus, respectively. Impact strength matrix decrease reprocessing, except slight especially 18% impact observed.