EFFECT OF VOLUME FRACTION OF PARTICULATES ON THE RHEOLOGICAL BEHAVIOR OF POLYMER COMPOSITES.

Composite systems consisting of a polymeric matrix and a dispersed solid particulate are commonly encountered in the plastics industry. The compounding of inert solid particulates into the polymeric matrix is most frequently employed in order to enhance the mechanical properties of the finished product. The theory proposed by Tanaka and White has been found useful for correlating the viscosity as a function of shear rate for a SiC-filled polymeric composite exhibiting a yield stress. The relationship given by Kitano et. al. gives excellent agreement for the viscosity as a function of loading level using an independently measured value for the maximum packing fraction phi //M. This relationship has been found to be valid for a wide diversity of composite systems including those possessing either a Newtonian or non-Newtonian matrix.