Expanded polyelectrolyte resin and process for making same
Abstract
Abstract A process for making highly expanded polyelectrolyte gel powders suitable for incorporation into, and imparting improved moisture vapor transmission rates to, films comprising hydrophobic polymers and the like. This process comprises the removal of water and other plasticizing components from precipitated polyelectrolyte complex gels, redispersing the gel in a volatile liquid medium, and thereupon causing the rapid evaporation of said volatile medium under conditions, conveniently moderately elevated temperatures, which prevent moisture from condensing on the polyelectrolyte gel as it is separated from the aforesaid volatile medium. The unique products of the invention are highly porous and characterized by their high absorptivity of dioctyl phthalate, their low-bulk density and their ability to enhance the moisture vapor transmission of a standard polyvinylchloride film formulation by a factor in excess of about 5 when incorporated therein at loadings of about 15 percent on total polymer weight.
Inventors
- 👤 Stephen A Splitz
Bibliographic Details
Claims Analysis
Total Claims: 3References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1975-01-17 | 1975-07-19 | 1976-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-17 | 1979-07-19 | 1980-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-17 | 1983-07-19 | 1984-01-18 | $7700.00 | Window Closed / Lapsed |