Shale-stabilizing additives

摘要

A shale-stabilizing additive is described which comprises a copolymer of an olefinically unsaturated hydrocarbon and an ethylenically unsaturated carboxylic acid, carbocylic acid salt or carboxylic acid anhydride with alkylene oxide based side chains. The additive can be used for water-based service fluids (WBM) to facilitate the drilling or completion process in shales or clayey formations.