Patent ID: 6403712
Filing Date: 2002-06-11
Classification: D01F

Abstract:
A process for preparing spandex comprising the steps of:A. preparing a polymer solution of an elastomeric segmented polyurethane, based on 1,1â€²-methylenebis(4-isocyanatobenzene), a polyether glycol selected from the group consisting of poly(tetramethyleneether) glycol and poly(tetramethyleneether-co-3-methyltetra-methyleneether) glycol, and a diol selected from the group consisting of ethylene glycol, 1,3-propane diol, and 1,4-butane diol; B. adding to the solution prepared in step A 1-10% by weight of total polymer solids content a polymer selected from the group consisting of poly(N-vinyl-2-pyrrolidone) and PVP copolymers having a K value of 20-70; C. dry-spinning the solution prepared in step B to form spandex; and D. winding up the spandex.