3D SIMULATIONS OF A REACTIVE FLOW IN SCREW ELEMENTS OF CLOSELY-INTERMESHING TWIN SCREW EXTRUDERS: A SCALE-UP ANALYSIS

摘要

The peroxide-initiated degradation of polypropylene in fully-filled screw elements of closely intermeshing twin-screw extruders is being analyzed. For this purpose, three-dimensional simulations are being implemented to describe this reactive flow in screw elements of two different size extruders. The effects of the initial peroxide concentration, mass throughput, and, especially, extruder size on the final weight-average molecular weight and poly-dispersity index of the product are studied. In relation to the later, the temperature of reaction resulting from the specified processing conditions is discussed.