1985 Volume 42 Issue 1 Pages 9-15
Flow properties of the polymeric system filled with carbon fiber (CF) are studied by using a capillary extrusion rheometer. Viscosity and entrance pressure loss are dependent upon the volumetric loading φ and the fiber length and its distribution Λ of CF. An expression of Barus effect ε= B2-1, where B is defined as die swell ratio, can be successfully represented as a function of apparent shear stress τw′. Although there are differences between plots of ε obtained by the direct method and the indirect one, φ and Λ intensely affected on them. The flow rate of extrudate at a die exit is in inverse proportion to the weight per unit length of the extrudate and decreases as τw′ increases, whereas the increasing φ and Λ reduce the τw′ dependence. The die swell of polymer component in an extrudate is reduced with the increase of φ, and the variation based on Λ is possibly considered as the effect of φ.
