Manufacturing method of polyurethane-based elastic fiber excellent in marine property and heat resistance

摘要

(A) having a number average molecular weight of 1,000 to 3,000 and a polyether diol (A-2) having a number average molecular weight of 500 to 3,000 are mixed with a polyether diol (A-(D), which is a chain growth agent, is prepared by preliminarily mixing 2 to 7 amino groups and at least 3 polyols (B) having at least one amino group and at least one organic polyisocyanate compound (C) 0.5 to 0.98 mol of the prepolymer and 1 to 30% of the amount of the monoamine (E) used as the chain amine are added so that the polymerization is completed. Then, 0.01 to 1% by weight of a heat resistance improving additive is added to the polymer solution The present invention relates to a method for producing polyurethane elastic fibers having excellent marine properties and heat resistance.