Patent ID: 6743288
Filing Date: 2004-06-01
Classification: C04B,C09K

Abstract:
An improved well cement composition comprising:a hydraulic cement; sufficient water to form a slurry; and a terpolymer fluid loss control additive comprising first, second and third monomers wherein said first monomer is selected from the group of 2-acrylamido-2-methylpropane sulfonic acid, 2-allyloxy-2-hydroxy-1-propane sulfonic acid and vinylsulfonic acid and said second monomer is selected from the group of N,N-dimethylacrylamide, acrylamide, N-vinylpyrrolidone, N-vinylacetamide and acrylonitrile and said third monomer is selected from the group of C6 to C22 dimethylaminopropylmethacrylamide bromide, chloride and iodide and C6 to C22 dimethylaminoethylmethacrylate bromide, chloride and iodide.