Composition and method of preparation of novel aqueous drilling fluid additives
US4521578A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 1983 |
| Grant date | Jun 4, 1985 |
| Priority date | — |
| Expiry date | Sep 26, 2003 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F220/585
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The present invention relates to new compositions and methods of preparation of deflocculents for water-base mud additives. The disclosed materials are low molecular weight terpolymers and graft copolymers consisting essentially of monovalent salts of (1) 5 to 50% by weight of tetrahydrophthalic acid (THPA); (2) 10 to 70% by weight of acrylic acid (AA); (3) 5 to 50% by weight of 2-acrylamido-2-methylpropane sulfonic acid (AMPS); and (4) 0 to 70% by weight of lignosulfonate units. The unique compositions and processes of terpolymers and graft copolymers provide excellent drilling fluid additives which significantly control the viscosity, yield point, gel strength, and fluid loss of drilling fluids over a wide range of temperatures and in the presence of contaminants such as salt, lime, cement, gypsum and drilled solids.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.