| 摘要 |
Cementing compositions, and methods of using such compositions in oil, gas and water well cementing operations to reduce fluid loss from the composition to the formation, incorporate certain copolymer salts, the copolymers being derived from N,N-dimethylacrylamide and 2-acrylamido-2-methyl propane sulfonic acid or acid salt, having mole ratios of between 1:4 and 4:1 respectively and average molecular weights of between about 75,000 and about 300,000. The copolymer salts are made by neutralising the acid copolymer, or by using an acid salt monomer. |
