Evaluation of rheological parameters of polymer melts in torque rheometers

A new empirical equation is developed to evaluate rheological parameters of polymer melts in torque rheometers, in which the effects of rotor speed, temperature and apparent filling degree on torque are all considered. With a well-defined experimental procedure, balance torque and temperature are obtained by an exponential model and can then be used to fit a modified equation. The resulting rheological parameters are in good accordance with those measured by capillary rheometer. For the sake of saving experimental expense and time, a statistical experimental design method, termed a uniform design, was used in our experiments. (C) 2001 Elsevier Science Ltd. All rights reserved.