PREPARATION METHOD OF ELASTIC YARN HAVING EXCELLENT POWER AND ELONGATION

摘要

The present invention relates to a preparation method of a polyurethaneurea elastic yarn, wherein the elastic yarn having high power is prepared by preparing a prepolymer by using 1) a glycol having a number average molecular weight of 500-1,200 dalton and 2) a diisocyanate mixture comprising 1-15 mol% of 2,4'-diphenylmethane diisocyanate on the basis of the total weight of diisocyanate; adding 3) a chain extender to the prepolymer to obtain a polyurethaneurea polymer; and stirring the polyurethaneurea polymer to mature the obtained polyurethaneurea spinning undiluted solution and spinning the undiluted solution. The polyurethaneurea elastic yarn prepared by the method has high power and excellent elongation, and the thermal deterioration of knitted and woven products using the elastic yarn due to a post-process carried out after knitting or weaving can be reduced.