abstract |
The present invention is directed to a non-aqueous, base-degradable polyurethane. The polyurethane is prepared by reacting an organic polyisocyanate with a hydroxyl group containing hydrophilic composition. The hydrophilic composition must have specified amounts of ionic or acidic groups and specific amounts of polyester groups. In a preferred embodiment, the hydrophilic composition also contains polyoxyethylene groups. |