Somjate Patcharaphun and Narongrit Sombatsompop

pp. 53 - 66

Abstract

The objective of this research was to design and develop an experimental apparatus and a temperature sensor in order to measure true melt temperature rise due to the shear heating during the flow. The designed apparatus featured two different forms, one being the polymer melt flowing past the stationary sensor (so-called moving piston), and the other being the sensor moving along the stationary polymer melt (so-called moving sensor). By subtracting the temperature data obtained by moving sensor from those obtained by moving piston the true melt temperature rise could be yielded. The temperature data were collected using a high-speed data logger and a computer. The effects of melt/piston velocity, initial melts temperature and various types of polymer melts used were of interest in this work. It was found that the experimental apparatus designed and used in this work was very effective and gave reasonably accurate results. In the moving piston system, the maximum melt temperature rise was in the range of 6-12 °C. Increasing the piston speed and initial melt temperature resulted in an increase in the maximum temperature rise. At very high piston speed, the maximum temperature rise reduced. In the moving sensor system, the maximum melt temperature rise due to the friction between the melt and the sensor was independent of the sensor velocity, initial melt temperature and types of polymer melts

The maximum melt temperature rise for this sy