R. Janarthanan et al., MORPHOLOGICAL-STUDIES ON EXTRUDED FILMS AND FILAMENTS OF POLYPROPYLENE, Journal of applied polymer science, 51(7), 1994, pp. 1175-1182
In the present work, an attempt has been made to study the development
of morphology during extrusion and uniaxial stretching of polypropyle
ne (PP) films and filaments at corresponding conditions. Dies for extr
usion of films and filaments were designed to achieve similar extrusio
n velocity and shear rates. Orientation in films and fibers of PP prod
uced from these dies was determined by birefringence and wide-angle X-
ray diffraction (WAXD). The degree of crystallinity was determined by
density and WAXD. The superstructure developed during extrusion was st
udied in films by small-angle light scattering. It was inferred that f
ilms and fibers prepared under similar conditions would produce simila
r morphology. Hence, films can be characterized by optical techniques
when it is difficult to study fibers. (C) 1994 John Wiley & Sons, Inc.