X-ray diffraction and TGA studies on annealed PPT twaron fibers and powder

✍ Scribed by A. M. Hindeleh; A. A. Abu Obaid

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 637 KB
• Volume: 47
• Category: Article
• ISSN: 0323-7648
• DOI: 10.1002/actp.1996.010470108

✦ Synopsis

Twaron fiber is spun from the polymer poly(parapheny1ene terephthalamide), PPT, and has a crystallinity of 82%. Wideangle X-ray diffraction, combined with the multipeak resolution procedure, was applied to study the changes in the structure after annealing the fiber in the temperature range of 100-675°C. The structural parameters included crystallinity (crystalline order), microparacrystal (mPC) size, and netplane spacing. A thermogravimetric analysis (TGA) was made to determine the loss in mass of the fiber in the temperature range in which the annealing study was carried out. Crystallographically-disordered (amorphous) powder of the PPT polymer was prepared by grinding crystalline Twaron fibers, which had a crystallinity of 87%, in a vibratory ball mill for a period of 64h. A study was then made to determine the extent to which the original crystallinity or mPC size is restored after annealing the powder in the temperature range of 100-425°C.