Patent ID: 7351681

Claim:
A well bore servicing fluid comprising a thermally activated viscosification composition comprising an ionic water-soluble, hydrophobically modified polymer; wherein the ionic water-soluble, hydrophobically modified polymer is: a copolymer of N-alkylacrylamides and an ionic monomer; a copolymer of stearylacrylate and acrylic acid; a terpolymer of N-isopropylacrylamide, trimethyl acrylamidopropyl ammonium iodide, and 3-dimethyl-(methacryloxyethyl) ammonium propane sulfonate; a copolymer of N-tertiarybutylacrylamide or N-isopropylacrylamide and 2-acrylamide-2-methyl propane sulfonic acid; poly(ethyleneoxide)-block-poly(propyleneoxide)-block-poly(ethyleneoxide) grafted with polysodium acrylate; hydrophobically modified poly(sodium acrylate); or copolymer of N-vinylcaprolactam and sodium acrylate; and wherein the copolymer of N-alkylacrylamides and an ionic monomer consists of 60 to 0.1 mole percent hydrophilic monomers and 40 to 99.9 mole percent hydrophobic monomers.