| abstract |
The disclosure relates to a composition for well cementing in a subterranean formation comprising a pumpable slurry of cement, water and at least one additive that swells in contact with underground fluid (hydrocarbon, water or brines and mixtures thereof ) in case of failure of the cement matrix and to a method of cementing a well using said composition. The swelling additive is an elastomer compounded with an aqueous inverse emulsion of particles of a polymer comprising a betaine group. |