Viscoelastic compositions
US7704926B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 2002 |
| Grant date | Apr 27, 2010 |
| Priority date | — |
| Expiry date | Aug 18, 2023 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K2208/30
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The present invention provides aqueous viscoelastic compositions comprising a cleavable surfactant and possibly also an electrolyte. The cleavable surfactants useful in the present invention comprise at least one weak chemical bond, which is capable of being broken under appropriate conditions, to produce oil soluble and water soluble products typically having no interfacial properties and surface activity compared with the original surfactant molecule. Further, the rheological properties of the aqueous viscolelastic composition are usually altered upon cleavage of the cleavable surfactant generally resulting in the elimination of the viscofying, viscoelastic and surfactant properties of the composition. Aqueous viscoelastic compositions in accordance with the present invention are suitable for use in oil-field applications, particularly for hydraulic fracturing of subterranean formations. Thus, the present invention also relates to a wellbore service fluid and a method of fracturing a subterranean formation. The present invention also concerns novel cleavable surfactants.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.