Polymorphic composition of colored polypropylene fibers

The investigations of the structure of polypropylene fibers colored with quinacridone and phthalocyanine pigments were carried out. The fibers were extruded from the melt at three different temperatures and were taken at three different velocities. In fibers two polypropylene modifications, the monoclinic a and the trigonal beta, were observed. The content of particular modifications depends on the kind of added pigment as well on the spinning parameters. The highest beta form content was observed in fibers colored with the quinacridone pigment extruded at the lowest temperature and taken at the lowest velocity. For fibers colored with the phthalocyanine pigment spun at such conditions the beta form content is much lower. With the increase in the take-up velocity and the increase in the extrusion temperature in fibers colored with both pigments the beta form content desirably decreases.