| 摘要 |
A method for the rheology control of fluid phases, in which adducts which contain layered mixed metal hydroxides (MMH) and hectorite are used, and corresponding compositions for this purpose are claimed. Preferably used MMH are those which were produced by hydration of mixed metal oxides or oxyhydroxides, which in turn may be thermally activated. The use of coprecipitated MMH or of MMH produced in situ is also possible. The ratio of MMH to the hectorite component should preferably be from 0.05 to 0.2:1, it also being possible to use adducts whose clay fraction contains up to 80%. by weight of clays differing from hectorite, in particular bentonite. The method is preferably carried out using drilling fluids in the high-temperature range >300° F. (>149° C.).
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