Effect of Water on High-Strength and High-Modulus Poly(vinyl Alcohol ) Fibers from Crosslinking Wet Spinning /Multistep Drawing

Abstract

The presence of water in poly (vinyl alcohol ) fibers spun from a water-soluble poly mer was investigated using differential scanning calorimetry, polarizing microscopy, scanning electron microscopy, and x-ray diffraction techniques. Poly( vinyl alcohol ) fibers were produced using the crosslinking wet spinning technique, which is an im provement on conventional noncrosslinked wet spinning. Borate ion-aided crosslinks were introduced during the coagulation process. Fibers had a higher drawability with the advanced wet-hot process and multi-step drawing. The tensile strength and modulus of drawn poly(vinyl alcohol ) fibers were 1.82 and 51.76 GPa, respectively. The presence of water in the fibers damaged their structure and drastically disturbed the orientation of their molecular chains. After tensile testing, there was a fractured circular layer in the fibers.