Flame-retardant polyvinyl alcohol base fiber

摘要

PCT No. PCT/JP98/04424 Sec. 371 Date Jun. 7, 1999 Sec. 102(e) Date Jun. 7, 1999 PCT Filed Oct. 1, 1998 PCT Pub. No. WO99/18267 PCT Pub. Date Apr. 15, 1999A vinyl-alcohol-based polymer and vinyl-halide-based polymer are dissolved in a common organic solvent for them, a typical example of which is dimethylsulfoxide, to obtain a dope wherein a solution of the vinyl-halide-based polymer having a particle size of 1-50 mu m is present in the solution of the vinyl-alcohol-based polymer. This dope is spun into a low temperature solidifying bath comprising a solidifying solvent such as methanol, and the organic solvent. The resultant is subjected to extraction, drying, dry heat drawing, and optional heat shrinking or acetalization to obtain fiber. In the fiber thus obtained, the vinyl-alcohol-based polymer makes sea phases, and the vinyl-halide-based polymer makes island phases whose size is 0.1-3 mu m. The crystallinity degree of the vinyl-alcohol-based polymer is 65-85%. The polyvinyl-alcohol-based flame retardant fiber is useful for clothes, industrial materials, living materials and the like. It can be produced at low costs, and has excellent spinning stability and dimensional stability in hot water.