Aqueous well fluids
US4699722A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 23, 1985 |
| Grant date | Oct 13, 1987 |
| Priority date | — |
| Expiry date | May 23, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S507/925
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Aqueous well fluids, such as completion, stimulation and work over fluids contain, as a viscosifier, a polymer having recurring units derived from monomers of the formula EQU CH.sub.2 .dbd.C(R.sup.1)CONHR.sup.2 NR.sup.3 R.sup.4 wherein R.sup.1 is hydrogen or methyl, R.sup.2 is straight or branched chain is C.sub.2-8 alkylene having at least 2 carbon atoms in the backbone and R.sup.3 and R.sup.4 are independently selected from C.sub.1-4 alkyl. Preferred units are derived from dimethylaminopropyl methacrylamide, generally as an acid addition salt. The fluids may contain high ion concentrations. The fluids may be used in processes in which they are maintained downhole for long periods of time at high temperatures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.