Orientation evaluation of ultra‐high molecular weight polyethylene fibers: previous studies and an improved method

• Published in: Journal of applied crystallography 2022-08, Vol.55 (4), p.876-881
• Main Authors: Zhang, Hao, Li, Jianrong, Guo, Yuihai, Tian, Feng, Qiao, Yongna, Tang, Zheng, Zhu, Caizhen, Xu, Jian
• Format: Article
• Language: English
• Subjects: Correlation coefficient; Correlation coefficients; evaluation methods; Fibers; Mechanical properties; Microfibrils; Molecular weight; Orientation; Polyethylene; Ultra high molecular weight polyethylene; ultra‐high molecular weight polyethylene (UHMWPE) fibers; ultra‐small‐angle X‐ray scattering; USAXS
• ISSN: 1600-5767; 0021-8898; 1600-5767
• DOI: 10.1107/S1600576722006112

Determination of the orientation of microfibrils within ultra‐high molecular weight polyethylene (UHMWPE) fibers is considered to be an important method in evaluating the mechanical properties of the fibers. Four commonly used orientation evaluation methods are summarized and used to evaluate UHMWPE fibers at different drawing stages in the industrial line, and the results exhibit certain limitations. To overcome these limitations, a new evaluation method for quantitive characterization of UHMWPE fiber properties is proposed. Meanwhile, in situ small‐angle X‐ray scattering data of an UHMWPE fiber drawn at 100°C were used to perform a Pearson correlation coefficient test, and the results show a very strong correlation between the strain ratio and the evaluated coefficient. The limitations of the general evaluation methods for microfibril orientation in ultra‐high molecular weight polyethylene fibers are discussed, and an improved evaluation method is proposed.