Structure-property relationship for poly(ethylene terephthalate) fibers prepared through continuous drawing in ethanol

In our previous study, we discussed necking behavior of poly(ethylene terephthalate) (PET) undrawn filament for various drawing conditions under continuous drawing process using ethanol. We confirmed that multiple necks occurred in the continuous drawing process and the stability of the process was improved by installing a pin in the draw line. To improve efficiency and productivity of the process, detailed analysis of the continuous drawing process was conducted. We measured the variation of natural draw ratio (NDR) under various drawing speeds. Structure - properties relationship of the fibers drawn to the NDR were analyzed. Appearance of the endothermic peak in the DSC curve was considered to be due to the vaporization of ethanol with subsequent confirmation of the presence of ethanol in the filaments. The ethanol-induced crystallization at room temperature was also confirmed from the crystalline reflections in the 2-D WAXD patterns.