| 摘要 |
There is provided a wellbore fluid having a continuous aqueous phase, and comprising at least one polymer which contains both hydrophilic units and hydrophobic units, at least some of said hydrophilic units containing sulfonate groups, and less than 50 % by weight of said hydrophilic units comprising -CH2.CH2.O- units; and at least some of said hydrophobic units containing pendant alkyl groups having at least 8 carbon atoms. Such aqueous based wellbore fluids exhibit significantly improved fluid loss properties when used in wellbore operations, such as drilling, completion or workover. |
