Patent · US Expired

Polyampholytes - high temperature viscosifiers for high ionic strength drilling fluids

US4637882A · kind A · utility

7Cited by
6References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 16, 1983
Grant dateJan 20, 1987
Priority date
Expiry dateDec 16, 2003

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08F226/10
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

A new family of terpolymers based on V-vinyl-2-pyrrolidone/sodium styrene sulfonate/methacrylamidopropyltrimethylammonium chloride has been found to be an improved viscosity control additive for water-based drilling muds. The resultant muds display good viscosity characteristics, thermal stability and gel strength when formulated from the terpolymer intramolecular complex having the appropriate polymer concentration and salt level.

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