| abstract |
Compressible and resilient sealing compositions for injection into oil or gas wells are provided, which are capable of forming effective seals adjacent well casings even at elevated downhole temperatures. The compositions comprise an epoxy component present in a predominant weight percentage, including an epoxy resin and a glycidyl ether modifier, as well as additional components rendering the cured compositions both compressive and resilient. The compositions are used as a partial or complete substitute for casing cements, and can be used to good effect with expandable casing installations or for sealing casing breaks. High set-up temperature (220-300° F.) compositions preferably include an ethoxylated alkyl (C10-C20) monoamine or diamine, and alkyl pyridine quaternary ammonium components. |