Hydrophilic foam

Abstract

MDI-based prepolymers are blown with a substantially nonaqueous blowing agent, such as pressurized air, an polymerized with stoichiometric amounts of polyoxyethylene polyol having at least two hydroxyl equivalents per mole, yielding a hydrophilic foam. The present foams may be extruded, knife-coated or otherwise cast into sheets, or may be fabricated by other known foam preparation techniques. Because the foam is polymerized with polyoxyethylene polyol instead of water, the foam exhibits both superior drape and improved stretch and recovery as compared with prior-art MDI-based flexible foams formed with aqueous reactants. The foam is particularly suited for use in external biomedical applications as, for example, a laminated medical/surgical dressing in which a thin sheet of the hydrophilic foam adheres to a nonstick aluminized veil on one side.

Dependencies are inferred from the claim text.