| 摘要 |
A fluid loss additive comprises a biodegradable grafted copolymer, wherein the copolymer comprises: (i) a first polymer comprising a monomer or monomers selected from the group consisting of acrylamido-2-methylpropane sulfonic acid, N-N dimethyl acrylamide, N-vinyl-N-methylaceamide, N-vinylformamide, N-vinylpyrrolidone, acrylonitrile, acrylamide, acrylomorpholine, vinyl alcohol, maleic anhydride, acrylic acid, and any combination thereof; and (ii) a second polymer, wherein the first polymer is grafted onto the second polymer. A method of cementing in a low-temperature subterranean formation comprises: introducing a cement composition into the subterranean formation comprising: (i) cement; (ii) water; and (iii) the fluid loss additive; and allowing the cement composition to set. According to another embodiment, a method of cementing in a high-temperature subterranean formation comprises: introducing a cement composition into the subterranean formation comprising: (i) cement; (ii) water; (iii) a clay; and (iv) the fluid loss additive; and allowing the cement composition to set. |
