摘要 |
<p>A process is provided for making an anionic polyurethane wherein a monomeric, aliphatic, dihydroxyl compound having an aliphatic substituent containing at least 10 carbon atoms is reacted with an organic polyisocyanate to form an adduct having terminal NCO groups, and the resulting adduct is reacted with an aliphatic monomeric diol chain extender containing an acid group which is capable of salt formation or a salt group. If the chain extender contains an acid group, the chain extended polyurethane is reacted with a basic compound to form a salt. The product of the invention may be used to size paper.</p> |