A novel method for the determination of steady-state torque of polymer melts by HAAKE MiniLab

Abstract HAAKE MiniLab is an apparatus specially designed for compounding polymer material and on-line testing of rheological properties. For the first time, it was used to establish a dynamic speed test method for the rapid determination of steady-state torque of polymer melts. The choices of sample feed quantity and screw rotation speed, as well as calibration for real torque, were carefully studied before torque measurements. The repeatability and reliability of torque data were also evaluated. Results showed that the torque could be calibrated by subtracting the torque without samples. Also, a feed quantity of ca. 6 g with a dynamic speed test range of 10–105 r/min was suitable for the determination of steady-state torque of polyolefin samples. The new method was quick, effective and reliable to correlate the steady-state torque with rotation speed. Therefore, MiniLab would be a very useful tool in exploring and characterizing polymer flow behavior through its torque measurements.