Effect of filler content and temperature on steady‐state shear flow of wood/high density polyethylene composites

Abstract

AbstractSteady state shear flow of wood/high density polyethylene composites is investigated through capillary rheometry to gain better insight into rheology, extrudate distortions, and wall slip phenomena of wood/polymer composite melts. Effects of filler content and temperature on onset and end of stick‐slip transition, in terms of shear rate and shear stress, are also studied. Results show that shear rates at stick‐slip transition decrease while corresponding shear stresses increase with the addition of filler. Furthermore, temperature raises the shear rate and the shear stress at which the transition occurs. It is observed a log‐linear relationship in the plots of wall slip versus the shear stress, in particular, increasing the filler content and decreasing the temperature, these plots are shifted to higher shear stress, as a consequence of viscosity increment. Wall slip and filler content play a fundamental role in surface morphology; specifically, extrudates become smoother with increasing filler content and shear rate, whose increment always results in a rise of the wall slip. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers