Heterogeneity and anisotropy of injection-molded discs of polypropylene and polypropylene composites

The anisotropy and heterogeneity of injection-molded discs of polypropylene , talc-filled polypropylene composites, and silane-treated talc-filled poly propylene composites are studied by means of dynamic mechanical analysis an d thermomechanical analysis. The aims of this work are to discover the rela tionships between the structure of the composites, their anisotropic proper ties, and the heterogeneity of the molded discs. The experimental results s how that although the discs are almost homogeneous, they present a high deg ree of anisotropy. (C) 2000 John Wiley & Sons, Inc.