Water-soluble copolymers and their use for the exploration and recuperation of oil and gas

摘要

Surprisingly, mixed polymers containing structural units from acrylamido-N-methylenepropenyl sulfonates, vinylphosphonic acids, or their salts and a cationic comonomer enable cement slurries to be obtained with low water loss. Surprisingly, mixed polymers containing structural units from acrylamido-N-methylenepropenyl sulfonates, vinylphosphonic acids, or their salts and a cationic comonomer enable cement slurries to be obtained with low water loss. The mixed polymers contain (wt.%): (A) structural units derived from compounds of formula (I) (5-95); (B) structural units from compounds of formula (II) (1-95); (C) structural units derived from compounds of formula (III) (1-95); or as an alternative to (C) (D) structural units derived from compounds of formula (IV) (1-95). X = a cation.