| 摘要 |
<p>The rubber like, thermoplastic polyurethanes, esp. polyurea-ureathanes are prepd. by reaction of (a) bifunctional, OH- contg. polyester prepd. from >=6C dicarboxylic acids and >=4C aliphatic diols and of mol. wt. 1500 - 2500, (b) aliphatic and/or aromatic diisocyanates and (c) cpds. contg. >=1 allylether gp. and reactive with isocyanates. The amt. of isocyanate used is such that the prodt. is free of excess isocyanate gps. The prodt. forms mouldings, esp. elastic fibres, which are of high strength and elasticity, low residual deformation and are resistant to hydrolysis.</p> |
