OIL COMPOSITION FOR PREVENTING INFLUX OF WATER INTO UNDERGROUND FORMATIONS Russian patent published in 2012 - IPC C09K8/502 

FIELD: chemistry.

SUBSTANCE: present invention can be used in oil industry, particularly for preventing influx of water into wells. The invention relates to a liquid oil composition containing at least the following compounds: (a) a compound which contains at least 2 isocyanate groups which are possibly blocked, (b) a surfactant and (c) aprotic oil which is capable of solubilising compounds (a) and (b); as well as a method of preparing the oil composition by mixing said compounds. The invention also relates to a method of treating underground formations into which said oil composition is pumped. The oil composition can be used when extracting hydrocarbons to prevent influx of water, control profiles, in chemical flooding of collectors, reinforcing sand, sealing embankments or zone conservation. The invention also relates to a water-in-oil emulsion in which the continuous phase contains oil (c) and the boundary surface between the water and the oil is completely or partially coated with a polycarbamide-type polymer obtained by hydrolysis and condensation of said compound (a), as well as a method of producing said water-in-oil emulsion. The invention is developed in subclaims.

EFFECT: high extraction of hydrocarbons by preventing influx of water into underground formations.

15 cl, 3 tbl