Influence of processing and particle morphology on final properties of polypropylene/talc nanocomposites

Abstract

The influence of different processing operations as well as particle morphology and concentration on microstructure and final mechanical properties of polypropylene/talc nanocomposites was studied, performing not only a comparative but also a combined analysis. Two continuous manufacturing process (injection molding and blown film extrusion) and two talc particle morphologies (macro and microcrystalline) were selected. Neat polypropylene and their nanocomposites containing different talc contents (1 and 5 wt%) were previously prepared in a twin-screw extruder and then they were processed using both processing operations. For injected nanocomposites, tensile behavior was strongly dependent on talc morphology. Tensile strength as well as ductility of nanocomposites containing macrocrystalline talc were higher than the corresponding to polypropylene/microcrystalline talc ones. Meanwhile, talc morphology influenced slightly on tensile behavior of nanocomposite films. These results allow selecting the appropriate particle morphology for each processing operation in order to obtain the best mechanical properties.