Details

Autor(en) / Beteiligte

• Sun, Haojun
• Meng, Xiangxuan
• Luo, Chuanfu
• Qian, Yeye
• Men, Yongfeng
• Su, Zhaohui

Titel

Quantifying Crystallinity in Poly(p‑phenylene terephthalamide) by Raman Spectroscopy

Ist Teil von

• Macromolecules, 2024-08, Vol.57 (15), p.7390-7397

Ort / Verlag

American Chemical Society

Erscheinungsjahr

2024

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Poly­(p-phenylene terephthalamide) (PPTA) forms high performance fibers, and their mechanical properties are critically dependent on the degree of crystallinity. Here we report a new method for quantifying the crystallinity in PPTA by Raman spectroscopy. The Amide I band at ∼1650 cm–1 in the Raman spectrum of PPTA was deconvoluted into three components associated with cis and different trans conformers respectively, and the assignments were supported by spectral calculation results. Then, the crystalline contribution to this band was isolated, from which the degree of crystallinity was derived. The measurement results were highly reproducible and in excellent agreement with that obtained by wide-angle X-ray diffraction over a wide range, showing good precision and accuracy. This method was then applied to analyze a defect of ∼5 μm size observed in a commercial PPTA fiber, and a much larger zone of lower crystallinity than the normal fiber section was revealed centered around the defect.