摘要:
Drilling mud additives based on a polymer mixture of 20 to 80% by weight carboxymethyl cellulose and 80 to 20% by weight of a polycarboxylic acid selected from polyacrylate, polymethacrylate and/or copolymers thereof and/or salts thereof, in which the carboxymethyl cellulose, which has been obtained from raw linters and/or wood cellulose by the slurry process, is mixed in wet, alcohol-moist form with the polycarboxylic acid and dried, to their use in drilling muds or workover and packer liquids, and to a process for their production.