Ionic exchange intensity in argillaceous reservoirs can be controlled
by crown ethers. They inhibit clay swelling while aqueous solution fil
tration and boost rock permeability. A bentonite clay swelling pattern
in magnetised and non-magnetised wafer, and when adding trace quantif
ies of cyclic oxirane oligomers into this medium, was studied. Concent
ration ranges and an optimum content (0.005-0.01%) has been found for
these ethers (cyclic polyethers based on propylene oxide) to minimise
clay swelling.