Aqueous based drilling fluid
US5134118A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 1991 |
| Grant date | Jul 28, 1992 |
| Priority date | — |
| Expiry date | Feb 22, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K8/24
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
This invention relates to an improved aqueous based drilling fluid and specifically to a water soluble polymer that imparts desirable performance characteristics to the final drilling fluid. The invention also relates to the method for preparation of the polymer and drilling fluid. The water soluble polymer is especially useful in that it exhibits superior tolerance to divalent cations, salts, solids and elevated temperatures when added to aqueous drilling fluids. The polymer additive is characterized by increased viscosity at low shear rates and improved fluid loss control thereby exhibiting superior rheological and thixotropic properties. The polymer consists of reaction products of sulfonated monomers and monomers added to enhance the functional characteristics of the polymer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.