| 摘要 |
<p>Water-soluble polyurethanes and their prepn. by reaction of (A) an anionic sulphonated polyester with average mol. wt. 500-3000, acid valve below 20 mg KOH/g., and S content 0.8-2 wt. %, with (B) >=1 diisocyanate, at 130-230 degrees C in molar ratio of NCO/OH+COOH 1. The opds. are used as sizes for textiles, esp. warp yarns in weaving, and for re-sticking the grain and flesh sides of leather. The polyurethanes dissolve readily in cold water to give stable solns. They are esp. suitable for sizing synthetic yarns, and do not dirty or block up the looms.</p> |
