| abstract |
Sulfonate-functional polyester polyols are derived from reactants comprising an unsaturated polycarboxylic acid or derivative thereof, a polyol, a lactone, and a sulfonating agent. The unsaturated polycarboxylic acid or derivative is substantially free of sulfonate-functionality, thereby providing sulfonate-functional polyester polyols having low color. The sulfonate-functional polyester polyols are suitable for use, for example, in the manufacture of water-dispersible polyurethanes and polyurethanes used as dispersants for particulate materials, for example, in magnetic recording media. |