| 摘要 |
A process for preparing aqueous polyurethane dispersions has been discovered which comprises (a) forming a polyurethane solution by reacting an organic polyisocyanate in the presence of a solvent with (i) an acrylic ester diol having a molecular weight of between 146 and 3,000; (ii) an organic polyhydroxyl compound other than (i) having a molecular weight between 400 and 5,000 selected from the group consisting of polyester polyols, polyether polyols, polycarbonates, polylactones, and mixtures thereof; and (iii) a chain extender having a molecular weight between 62 and 400 selected from the group consisting of diols, triols, diamines, aminoalcohols, and mixtures thereof; (b) forming an anionic polyurethane addition product by reacting said polyurethane solution with a mercaptocarboxylic acid salt in the presence of a solvent; (c) adding water; and (d) removing the solvent. The dispersions can be used in a variety of applications. For instance, they can be used to prepare films, coating, and binders. |
