A comparison of measurements of the viscoelastic properties of polymer melts by means of the Han slit/capillary rheometer and the Weissenberg rheogoniometer

Measurements were taken of the viscoelastic properties of six polymer melts by mean of the Weissenberg rheogoniometer and the Han slit/capillary rheometer. Polymers in vestigated were three high-density polyethylenes of different polydispersity, a low-density polyethylene, a polypropylene, and a polystyrene. The range of shear rates tested was from about 5.0 × 10−3 to 10 sec−1 with the Weissenberg rheogoniometer, from about 10 to 102 sec−1 with the slit rheometer, and from about 102 and 103 with the capillary rheometer: the temperature of measurement was 200°C. The three different apparatuses give consistent results over almost six decades of shear rates, yielding satisfactory correlations of shear viscosity to shear rate and of normal stress difference to shear rate.