Process for preparing elastic fiber having high modulus, alkali-resistance and heat-resistance

Abstract

Disclosed herein is a process for preparing an elastic fiber having a high modulus and superior resistance to alkali and heat. The process comprises the steps of adding 1˜20% by weight of a cellulose acetate to a polyurethane or polyurethaneurea solution, based on the total weight of the polyurethane or polyurethaneurea, homogeneously stirring the mixture to obtain a spinning solution, and ripening and spinning the solution. According to the process, a high modulus and highly heat resistant elastic fiber can be prepared without a sudden change in conditions for preparation of the polymer.

1 . A process for preparing an elastic fiber, comprising the steps of: 
 adding from 1 to 20% by weight of a cellulose acetate to a polyurethane or polyurethaneurea solution, based on the total weight of the polyurethane or polyurethaneurea, and homogeneously stirring the mixture to obtain a spinning solution;    ripening the spinning solution; and    spinning the ripened solution.    
   
   
       2 . The process according to  claim 1 , wherein the cellulose acetate is cellulose diacetate or cellulose triacetate having a degree of acetylation of from 28 to 72%.  
   
   
       3 . The process according to  claim 1 , wherein the polyurethane or polyurethaneurea solution is obtained by reacting an organic diisocyanate with a polymeric diol to form a polyurethane precursor, dissolving the polyurethane precursor in an organic solvent, and reacting the precursor solution with a diamine and a monoamine sequentially.  
   
   
       4 . The process according to  claim 3 , wherein the organic diisocyanate is selected from the group consisting of diphenylmethane-4,4′-diisocyanate, hexamethylenediisocyanate, toluenediisocyanate, buthylenediisocyanate, and hydrogenated p,p-methylenediisocyanate; the polymeric diol is selected from the group consisting of polytetramethyleneether glycol, polypropyleneglycol, and polycarbonatediol; the diamine is selected from the group consisting of ethylenediamine, propylenediamine, and hydrazine; and the monoamine is selected from the group consisting of diethylamine, monoethanolamine, and dimethylamine; and the organic solvent is selected from the group consisting of N,N′-dimethylformamide, N,N′-dimethylacetamide, and dimethylsulfoxide.  
   
   
       5 . The process according to  claim 1 , wherein the spinning solution further contains at least one additive selected from dulling agents, UV stabilizers, antioxidants, NO x  gas anti-yellowing agents, anti-adhesion agents, dyeing promoters, and anti-chlorine agents.  
   
   
       6 . The process according to  claim 1 , wherein after the addition of the cellulose acetate, the homogeneous stirring is carried out for at least 2 hours, and the spinning solution is ripened by allowing it to stand at 30° C. to 70° C. for 28 to 38 hours.  
   
   
       7 . An elastic fiber prepared by a process comprising the steps of: 
 adding from 1 to 20% by weight of a cellulose acetate to a polyurethane or polyurethaneurea solution, based on the total weight of the polyurethane or polyurethaneurea, and homogeneously stirring the mixture to obtain a spinning solution:    ripening the spinning solution; and    spinning the ripened solution.    
   
   
       8 . A velvet fabric manufactured using an elastic fiber prepared by a process comprising the steps of: 
 adding from 1 to 20% by weight of a cellulose acetate to a polyurethane or polyurethaneurea solution, based on the total weight of the polyurethane or polyurethaneurea, and homogeneously stirring the mixture to obtain a spinning solution;    ripening the spinning solution; and    spinning the ripened solution.