Patent · US Expired

Polyimide quaternary salts as clay stabilization agents

US5160642A · kind A · utility

44Cited by
23References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 25, 1990
Grant dateNov 3, 1992
Priority date
Expiry dateMay 25, 2010

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S507/922
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A clayish formation, such as encountered in rock surrounding an oil well bore, is stabilized with a quaternary ammonium salt of an imide of polymaleic anhydride. The invention is particularly relevant to hydraulic fracturing fluids used for enhanced oil recovery.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.