Patent ID: 8376045

Claim:
A method of cementing in a subterranean formation comprising: introducing a cement composition into the subterranean formation, the cement composition comprising: (i) cement; (ii) water; (iii) a clay; and (iv) a fluid loss additive comprising a biodegradable grafted copolymer, wherein the copolymer comprises: (a) 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 (b) a second polymer, wherein the first polymer is grafted onto the second polymer; and allowing the cement composition to set.