Rheology modifiers
US7387987B2 · kind B2 · utility
25Cited by
30References
32Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 13, 2006 |
| Grant date | Jun 17, 2008 |
| Priority date | — |
| Expiry date | Apr 13, 2026 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K2208/30
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A method for increasing the rate of shear rehealing of fluids made with cationic, zwitterionic, and amphoteric viscoelastic surfactant fluid systems by adding an effective amount of a polymeric rheology enhancer selected from polypropylene glycols and block copolymers of polypropylene glycol and polyethylene glycol. For applications in which rapid shear rehealing is required, the rheology enhancer allows fluids to be made and used at lower viscoelastic surfactant concentrations. Preferred surfactants are betaines and quaternary amines. The fluids are useful in oilfield treatments, for example fracturing and gravel packing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.