METHOD FOR PRODUCING POLYURETHANE ELASTIC YARN HAVING EXCELLENT HEAT RESISTANCE

摘要

PURPOSE: A method for producing a polyurethane elastic yarn is provided to have the heat resistance by improving the heat resistance of the polyurethane elastic fiber produced with a melt-spinning method without using a separate bridging agent. CONSTITUTION: A pre-polymer having the isocyanate in the end is obtained by reacting the 0.9-1.1mol diol compound of direct chain and high molecular weight having the 1,000-3,000g/m molecular weight of weight average, and the 2-2.5mol aliphatic or aromatic diisocyanate compound. Then a polyurethane polymer of the high molecular weight having enough isocyanate in the end of high molecular is generated by reacting the viscosity of the polymer reaching a balance with adding the aliphatic and the aromatic diol under 500 molecular weight of weight average or the mixture of these compound into the pre-polymer whose isocyanate bond is added the 0.9-1.3mol hydroxy. The polyurethane elastic yarn having the excellent heat resistance is produced by spinning the polyurethane polymer with a melt-spinning method.