| 摘要 |
Stable aqueous dispersions of crosslinked polyurethane particles are disclosed. Preferably the aqueous dispersions coalesce, upon drying, to form continuous films. The aqueous dispersions of crosslinked polyurethane particles are formed by reacting a mixture of polyfunctional hydrogen compounds, one of which has an ionically neutralizable solubilizing group thereon and one of which has a functionality of three or more, with a diisocyanate to form a non-crosslinked or ungelled prepolymer. The solubilizing group is neutralized and the prepolymer is dispersed in water. The prepolymer is chain extended with water or an aqueous solution of a water soluble diamine to form an isocyanate free dispersion of crosslinked polyurethane polymer. |
