Hydrogels with improved mechanical properties below water freezing temperature
US10975205B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 1, 2016 |
| Grant date | Apr 13, 2021 |
| Priority date | — |
| Expiry date | Jun 9, 2037 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08K2003/3063
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Hydrogel compositions, and corresponding methods of making, are provided. The hydrogels do not freeze, or only partially freeze, over a wide range of temperatures below the freezing temperature of water. Concurrently, these hydrogels also retain their room temperature mechanical properties (e.g., strength, modulus, elasticity) over a wide range of temperatures, including temperatures below the freezing temperature of water. The hydrogels are synthesized by adding a suitable amount of a salt together with previously cross-linked polymer gel. Hydration of the gel with aqueous solutions containing the prescribed salts not only depresses the hydrogel freezing point but protects the structure. For example, the salts do not allow the hydrogel to completely freeze, thus protecting the hydrogel from brittle failure. Whether the hydrogels partially freeze or remain non-frozen when chilled below the freezing temperature of water is determined by concentration of salt within the hydrogel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.