Effect of Drawing Speed on Infusion and Drawing Behaviors of Poly(ethylene terephthalate)Filaments upon Cold Drawing in Ethanol

抄録

We have reported previously that multiple neck appears, yield and drawing stresses decrease and natural draw ratio increases if drawing of low oriented amorphous poly(ethylene terephthalate) (PET) filament is carried out in ethanol rather than in the air or water. Crystallization of PET at room temperature took place in the cold drawing through the infusion of ethanol into filament. Based on these results, investigation on the effect of drawing speed on infusion and drawing behaviors of PET filament upon cold drawing in ethanol was carried out in this research. The decrease in drawing speed caused the reduction of number of neck, reduction of yield and drawing stresses and increase of natural draw ratio. Even though number of neck was larger at higher drawing speeds, analyzed propagation speed of individual neck point increased with the increase of drawing speed. On the other hand, amount of infused ethanol in filament at a high draw ratio increased with the reduction of drawing speed, which lead to the appearances of more distinct crystalline reflections in the wide-angle X-ray diffraction pattern and equatorial streaks of higher intensity in the small-angle X-ray scattering pattern. When the drawing was carried out in the ethanol mixed with dye, infusion of dye molecules was more distinct at lower drawing speeds, and vividly colored fiber was obtained at room temperature.