| 摘要 |
A polyurethane elastic fiber made from a polyurethane obtained from a copolymerized polyalkyleneether diol composed of different alkyleneethers containing 2 - 10 carbon atoms; the polyurethane comprises a urethane portion having a number average molecular weight of 6000 - 9500 and a urea portion having a number average molecular weight of 650 - 950. The polyurethane elastic fiber has improved elastic functions such as high elongation at break (elongation at break is 500%, or more), low modulus (300% modulus is 0.20 g/d, or less), excellent low temperature characteristics, and heat resistance; and, therefore, creation of highly excellent converted goods is made possible. The elastic fiber can be produced at a higher productivity by spinning the polyurethane prepared by reacting a copolymerized polyalkyleneether diols containing different number of carbon atom of 2 - 10 and 4, 4'-diphenylmethane diisocyanate to form a fully isocyanate terminated prepolymer for forming the said urethane portion followed by an additional loading of said diisocyanate and reacting a bifunctional diamine such as ethylenediamine to form said urea portion. <IMAGE> |
