Hydrophilic foam
US4644018A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 2, 1986 |
| Grant date | Feb 17, 1987 |
| Priority date | — |
| Expiry date | Jan 2, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T442/152
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
MDI-based prepolymers are blown with a substantially nonaqueous blowing agent, such as pressurized air, and 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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.