Effect of Flow Field on Online Shear Viscosity of PP/nano-CaCO3 Composites Available to Purchase

Polymer nanocomposites have been regarded as a new category of engineering materials and attracted technical and scientific interest. Recently rheological analysis became an effective tool for investigating the microstructures of nanocomposites. However, the online rheological property of nanocomposites during compounding was seldom studied. In this work, two types of screw configurations in twin-screw extruder were selected, one provides high shearing intensity and the other provides high shearing/mixing intensity. In addition, chaotic mixing was induced by installing a single screw extruder with a convective screw at the end of the twin-screw extruder to compound the nanocomposites. The online melt shear viscosity of nanocomposite was measured using Haake ProFlow online rheometer. Effects of high shearing, high shearing/mixing, and chaotic mixing on the online shear viscosity for polypropylene (PP)/nano-calcium carbonate (nano-CaCO₃) composites were investigated. The study showed that the chaotic mixing facilitates the processing of the nanocomposite.