Probing the Internal Structure of High-Performance Fibers by On-Axis Scanning Diffractometry

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• 作者：Richard J. Davies ; Manfred Burghammer ; Christian Riekel
• 刊名：Macromolecules
• 出版年：2007
• 出版时间：July 10, 2007
• 年：2007
• 卷：40
• 期：14
• 页码：5038 - 5046
• 全文大小：1086K
• 年卷期：v.40,no.14(July 10, 2007)
• ISSN：1520-5835

文摘

Many high-performance fibers exhibit radial anisotropy or a skin-core morphology. This influencestheir mechanical properties, affects the interfacial characteristics of composite systems, and needs considerationwhen interpreting results collected using localized probing techniques. This study reports on the direct observationof crystallographic texture and rotational disorder within a single high-performance fiber. This is possible usinga microfocused X-ray beam to obtain diffraction patterns along the fiber axis. This enables radial anisotropy tobe investigated without the need for modeling. The results indicate that the high-performance fiber studied exhibitsa rotationally disordered skin and core, with preferred orientation extending throughout the fiber. Variations inthe skin's width and core position are taken as evidence of heterogeneous coagulation. The experimental resultscan be explained by a fiber formation model in which oriented crystalline domains extend inward, toward thefiber center. These results allow a number of findings from previous model-based studies to be validated.