Injection molding of polypropylene: X-ray investigation of the skin–core morphology

✍ Scribed by W. Wenig; F. Herzog

• Publisher: John Wiley and Sons
• Year: 1993
• Tongue: English
• Weight: 934 KB
• Volume: 50
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1993.070501216

✦ Synopsis

The skin-core morphology of injection-molded polypropylene bars has been investigated employing X-ray small-and wide-angle scattering. The small-angle scattering has been evaluated by means of interface distribution functions. It is found that skin and core exhibit different morphologies. In the skin, the crystal lamellae are oriented primarily around the c axis, but a (small) fraction of a*-axis-oriented lamellae also exists. The lamellar thickness in the skin layer measured from the meridional small-angle X-ray scattering shows higher values than in the core. The composition of the monoclinic a l , a2 crystal modifications show dependencies that are typical for the cooling conditions in the mold during injection.