Structure Development in the Laser Drawing Process of Poly(ethlene terephthalate) Fiber Analyzed by Milliseconds' Time-resolution WAXD/SAXS Measurements

摘要

Fiber structure development in the poly (ethylene terephthalate) fiber drawing process was investigated by wide-angle and small-angle x-ray scattering (WAXD / SAXS)on-line measurement. For the purpose, both high luminance x-ray source and carbon dioxide laser-heated-drawing system were applied. By the change of transmission x-ray intensity, the position of neck-like deformation was confirmed. Because the fluctuation of the position was less than 1.2 mm, the obtained diffraction images had a time-resolution of several milliseconds. By increasing the fiber running speed, we have succeeded to get 0.7 milliseconds' time-resolution. The crystal diffraction appeared in the WAXD images at about 20 ms after neck-like deformation, whereas the four-point SAXS pattern appeared immediately after neck-like deformation. With the increase of elapsed time after neck-like deformation, the meridional four-point scattering pattern changed into the two-point shape.