Abstract
Three kinds of nylon 6 synthesized by an anionic polymerization were gel-spun using benzyl alcohol as a solvent and subsequently the gel-spun fibers were hot-drawn to various draw ratios. To analyze the gelation behavior of solution, sol-gel transition temperature and gelation time were measured. The sol-gel transition temperature increased with the increase of polymer concentration and the molecular weight. Optimum concentration of solution for gel-spinning was about 70 weight percent. It appeared that gels grew three-dimensionally according to the gel growth index calculated from the measured gelation time, which was evidenced by the presence of spherical gels in scanning electron microscopic measurement. However the spherical gels changed to the fibril structure after drawing. Modulus and tenacity increased almost linearly with the increase of draw ratio. Drawing behavior of nylon 6 gel fiber was different from that of ultra-high molecular weight polyethylene gel on basis of the relationship between tenacity and modulus, which is likely to be ascribed to the difference of gel structure.
