Oriented γ-isotactic polypropylene crystallized at atmospheric pressure

✍ Scribed by David M. Dean; Richard A. Register

• Book ID: 101272322
• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 175 KB
• Volume: 36
• Category: Article
• ISSN: 0887-6266
• DOI: 10.1002/(sici)1099-0488(19981115)36:15<2821::aid-polb16>3.0.co;2-p

✦ Synopsis

A method for crystallizing oriented samples of the ␥-phase of isotactic polypropylene (iPP) under atmospheric pressure in the presence of nucleating fibers has been developed. The technique uses iPP grades of high molecular weight and high isotacticity and produces a mixture of ␣ and ␥-phase crystals within the matrix of both pitch-based carbon and Kevlar-reinforced composites. Two-dimensional wide-angle X-ray scattering (WAXS) patterns from these samples show that the content of the ␥-phase decreases as the fiber loading in the composites decreases, suggesting that the ␥-phase is directly nucleated by the fibers.