Patent · US Expired

Method for effecting controlled break in polysaccharide gels

US4961466A · kind A · utility

154Cited by
9References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 23, 1989
Grant dateOct 9, 1990
Priority date
Expiry dateJan 23, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S507/921
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A controllable breaker for use in viscosified fluids utilized in the treatment of subterranean formations comprising a low molecular weight condensation product of hydroxyacetic acid with up to 15 wt % cocondensing compounds containing other hydroxy-, carboxylic-acid, or hydroxycarboxylic-acid moieties. The condensation product has an average molecular weight in the range of from about 200 to about 4000, a generally crystalline structure, a melting point above about 100.degree. C. and is substantially insoluble in the viscosified fluid at ambient temperatures. The breaker is admixed with the viscosified fluid in an amount sufficient to effect controlled breaking of the fluid upon being heated to a temperature above 70.degree. F. within a subterranean formation.

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