Evolution of Crystal Structure by Post-extension in Nylon 56 Fibers

Abstract

The crystal structure of nylon 56 fibers post extended by drawing process was investigated by synchrotron x-ray scattering measurement. In as-cast fiber, distinct (004) and (020) diffraction peaks were observed and they were related to initial metastable alignment of nylon molecules. With increase in the drawing ratio, (110) peak intensity was increased in vertical direction with decreasing (020) peak. At the same time, (004)' peak evolved position tilted to 29 degrees from the (004) peak. This evolution is directly related to stable crystalline phase of nylon 56 originated from additional formation of hydrogen bondings between N-H and C=O by post drawing process. We also compared density variation, stress-strain curves of the fiber as a function of drawing ratio and strain. The variations of density and tanacity also supported the increase of stable structure of nylon 56.

100% Bio-Based Polyamide with Temperature/Ultrasound Dually Triggered Reversible Cross-Linking

“…Polyamides are a series of high-performance materials which have been widely applied in industry. Traditional polyamides contain aliphatic (PA56 − , PA66 − , PA1111, PA1212, − and PA1313 − ) and aromatic classes (aramid − ). They have both advantages and disadvantages.…”