THE SPINNING OF A POLYMER BLEND CONSISTING OF POLYVINYL ALCOHOL AND A POLYMER CONTAINING VINYL PYRROLIDONE UNITS

In order to improve the dyeability of vinylon, the wet spinning of a polymer blend consisting of polyvinyl alcohol and a polymer containing vinyl pyrrolidone units, such as polyvinyl pyrrolidone and saponified or unsaponified vinyl acetate-vinyl pyrrolidone copolymer was carried out, and the fiber was subsequently heat-treated and acetalized to make the fiber resist to boiling water. Consequently, the fiber having improved dyeability with several dyes such as direct dyes, sulphur dyes and vat dyes, similar to that of cellulosic fibers, was obtained. The effect of blending of polyvinyl pyrrolidone may be explained by the affinity of the dye for polyvinyl pyrrolidone and by the known changes in the cross sectional structure and in the internal fine structure due to the polymer blending. The fiber may be suitable for blending with cellulosic fibers.By hot-drawing the wet-spun fiber containing polyvinyl pyrrolidone, followed by heat-treatment and formalization, the fiber having a relatively higher stiffness and the improved dyeability was obtained. The fiber shows the stiffness-dpeabillity relation similar to that of a cotton fiber, so the fiber seems to be suitable for blending with cotton.