Die geometry effects on the temperature profile measurements of flowing PPmelt in a twin-screw extruder

An investigation was carried out to determine the effect of die diameter on the temperature profiles of polypropylene (PP) melt measured in the barrel of a counter-rotating twin-screw extruder. The results were considered in connection with the flow patterns and pressure drop occurring in the barrel of the extruder. It was found that the melt-temperature profiles across th e duct were not uniform and were affected by the size of the dies used, thi s being associated with the flow patterns of the melt. The differences in t he maximum temperature rise (DeltaT(max)) were affected by the pressure dro p occurrance. The experimental results obtained were found to be different from theoretically calculated results. (C) 2001 Elsevier Science Ltd. All r ights reserved.