Drilling mud dispersants
US4518510A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 5, 1983 |
| Grant date | May 21, 1985 |
| Priority date | — |
| Expiry date | Dec 5, 2003 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F2800/10
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Dispersants useful in aqueous drilling mud formulations employed in the drilling of subterranean wells where high temperature and high pressure environments are encountered are disclosed. The dispersants, when used in amounts of about 0.1 to 25 ppb provide muds containing colloidal material suspended in an aqueous medium with improved high temperature and high pressure stability. The dispersants are water soluble sulfonated vinyl toluene-maleic anhydride copolymers which have a molar ratio of vinyl toluene to maleic anhydride of about 1:1 to less than about 2:1, a molecular weight of 1,000 to 25,000 and at least about 0.7 sulfonic acid groups per vinyl toluene unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.