High stiffness absorbent polymers having improved absorbency rates and method for making the same
US6939914B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 8, 2002 |
| Grant date | Sep 6, 2005 |
| Priority date | — |
| Expiry date | Apr 24, 2023 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2300/14
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
Superabsorbent polymer materials are provided including absorbent polymers having a fast vortex time, desirably about 10 seconds or less, and a stiffness index of at least about 0.7, as determined by test procedures described herein. The absorbent polymers can be modified to obtain a faster vortex time by a method including providing an absorbent polymer having a first vortex time, absorbing water with the absorbent polymer, freeze-drying the swollen absorbent polymer to remove at least a portion of the absorbed water, and obtaining a modified absorbent polymer having a second vortex time. The ratio of the first vortex time to the second vortex time is at least about 5, and desirably the modified absorbent polymer has a stiffness index of at least about 0.7.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.