Investigations of the layered structure of injection-molded polypropylene discs and of its behavior in tensile tests. Dedicated to Prof. H. Janeschitz-Kriegl on the occasion of his 65th birthday

The tensile test behavior of specimens taken from polypropylene discs injection‐molded with and without packing, respectively, was studied. The initial state of the different layers of the specimens and their stressed state, respectively, are characterized by small‐angle X‐ray scattering (SAXS), wide‐angle X‐ray scattering (WAXS), measurements of birefringence and of mechanical properties, and by light‐microscopic investigations. The results off these experiments altogether give a detailed representation of the behavior of the different layers of the specimens in the tensile test.