Influence of molecular weight and syndiotacticity on the structure of high‐performance poly(vinyl alcohol) fibers prepared by gel spinning

Abstract

Atactic and syndiotactic-rich poly(vinyl alcohol) fibers were prepared by gel spinning using ethylene glycol as a solvent. The mechanical properties of the fibers were independent of the degree of polymerization, although they were dependent on syndiotacticity. The amounts of tie molecules and the difference between the amounts of hydrogen bonds and microvoids determine the mechanical properties. The mechanical properties depended on the orientation of the segments in the amorphous parts. The entangled segments produced in the amorphous parts as a consequence of the difficulty of drawing were considered to form the voids and cracks, which grow to a banded structure.

Enhancing mechanical properties of gel‐spun polyvinyl alcohol fibers by iodine doping

“…The value of Δ n = 51.8 × 10 −3 and Δ n = 43.8 × 10 −3 were used [25]. For form birefringence, the Δ n f of polypropylene [26] was used as this value is not reported for PVA [27].…”

Gel spinning of synthetic polymer fibres

“…WonIll Cha et al 14 15 prepared atactic and syndiotactic-rich poly(vinyl alcohol) compound fi bres by gel spinning. The fi bre amorphous parts as a consequence of the diffi culty of drawing were considered to form the voids and cracks, which had a banded structure.…”

Design of Spinning and Subsequent Drawing Parameters to Improve the Mechanical Properties of PVA Fibers

“…Several spinning techniques such as gel spinning [16][17][18] and crosslinking spinning 19) , of great importance in commercial aspect, have been developed to enhance the mechanical properties of PVA fiber. Additional attempts to obtain high performance fibers following fiber spinning include ultrahigh drawing of gel-spun fiber 17) , zone drawing 20) , multi-step drawing 21) , hot drawing 22) , and annealing 23) .…”