| 摘要 |
A method for the recovery of oil from an oil-containing subterranean formation by waterflooding employing as an injection medium an aqueous solution of an anionic polymeric surfactant formed by reacting a polymer including succinic anhydride moieties with a primary amine to provide a polymeric reaction product in which at least 20 mol percent of the anhydride moieties have been converted, by reaction with said amine, to succinimide or succinamide groups. The polymeric anionic surfactants of the invention exhibit good physical and chemical stability, are shear stable, are effective in maintaining the salt stability of other surfactants (such as petroleum sulfonates) and also function as viscosifiers, even in the presence of significant concentrations of divalent metal ions. According to a preferred form of the invention, the surfactants comprise the reaction product of a copolymer of styrene and maleic anhydride and triethylammonium aniline disulfonate, in which reaction product from 20 mol percent to 40 mol percent of the anhydride moieties have been converted to succinimide or succinamide groups.
|
