Abstract
The influence of temperature and shear rate on the flow behavior of high density polyethylene (HDPE) melts during extrusion has been investigated by using a Ceast Rheovis 2100 capillary rheometer which was manufactured by the Ceast Co. in Italy. It was found that the entry pressure drop for the samples was very low during extrusion, the relationship between shear stress and shear rate did not obey the power law strictly, and the phenomenon of shear‐induced crystallization was easily produced when temperature was near the melting point of the samples, even though the shear rate was not high. The dependence of the shear viscosity for the samples on temperature can be described by using the Arrhenius equation. © 1993 John Wiley & Sons, Inc.