| 摘要 |
<p>Oil-based fluids comprise an oil phase and 1-50 lb/bbl of an organophilic clay gelling agent (I) which is the reaction prod. of an organic cation, an organic anion and a smectite-type clay having a cation exchange capacity of at least 75 meq/100g such that an organic cation/organic anion complex is intercalated with the clay and the cation exchange sites of the clay are substd. with the organic cation. Gelling agents of type (I) in which the organic cation is of formula XR1R2R3R4 or SR1R2R4 are new (where X is N or P; R1 is 8-60C alkyl; R2-R4 are H, 2-6C hydroxyalkyl, 1-22C alkyl, aryl or aralkyl). The fluids are esp. useful as drilling muds and packer fluids. They can be prepd. in a few min. by low-shear mixing and are stable at surface temps. below -20 deg and downhole temps. up to 500 deg.</p> |
