DELAYED, SWELLABLE PARTICLES FOR PREVENTION OF FLUID MIGRATION THROUGH DAMAGED CEMENT SHEATHS

摘要

A method includes providing a cementing composition that includes an aqueous fluid, a cementitious particulate, and a copolymer particulate which includes a monofunctional monomer, a water degradable first crosslinker, and a second crosslinker. The method further includes placing the cementing composition in a subterranean formation so as to form a set cement sheath and swelling the copolymer particulate in response to a void created in the set cement sheath. The copolymer particulate allows the cementing composition to set to form the cement sheath before substantial swelling of the copolymer particulate occurs.