摘要 |
Aqueous drilling muds which are rheologically stable, non-toxic and adopted for use at high temperatures, are comprised of a viscosity modifying material, e.g., a conventional clay, and a copolymeric dispersant therefor, said copolymeric dispersant comprising the water-soluble, low molecular weight copolymerizate of from about 75 to 99 molar % of acrylic or methacrylic acid, or admixture thereof, with from about 1 to 25 molar % of a water-soluble salt of allyl or methallylsulfonic acid, or admixture thereof.
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