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 polypropylene composites are studied by means of dynamic mechanical analysis and thermomechanical analysis. The aims of this work are to discover the relationships between the structure of the composites, their anisotropic properties, and the heterogeneity of the molded discs. The experimental results show that although the discs are almost homogeneous, they present a high degree of anisotropy. (C) 2000 John Wiley & Sons, Inc.