Structure Development in the Melt Spinning and Drawing of Poly p Phenylene Sulfide Fibers

Abstract

The development of crystallinity and orientation in melt spun and subsequently drawn poly p phenylene sulfide (PPS) fibers is investigated using differential scanning calorimetry (DSC), birefringence and wide angle x-ray diffraction (WAXS) techniques. The melt spun PPS fibers were found to possess small amounts of crystallinity at moderate draw-down ratios. The fibers may be crystallized to a significant extent by subsequent drawing over a hot plate. The levels of crystallinity and orientation in the largely glassy melt spun PPS fibers has been determined as well as subsequently drawn fibers. Uniaxial mechanical properties were determined as a function of spinning and drawing conditions. In general, elongation to break decreases while modulus and tensile strength increase with an increase of melt spinning draw down ratio and solid draw ratio. The Young's modulus and tensile strengths are increasing functions of fiber birefringence and the elongation to break a decreasing function.