Calcium-tolerant N-substituted acrylamides as thickeners for aqueous systems
US4584358A · kind A · utility
7Cited by
1References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 12, 1985 |
| Grant date | Apr 22, 1986 |
| Priority date | — |
| Expiry date | Jun 12, 2005 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K8/035
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A water-soluble ionically-charged random copolymer of acrylamide and an alkaline or alkali metal 3-acrylamido-3-methylbutanoate having an average molecular weight of greater than about 50,000 has been found to maintain unusually stable and effective viscosities in the presence of salts such as NaCl and CaCl.sub.2 when added to water in minor amounts, thus making it a highly effective mobility control agent for secondary and tertiary oil recovery methods. Also within the scope of the invention are terpolymers which additionally contain olefinically unsaturated monomers such as acrylic acid or sodium acrylate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.