(METH)ACRYLIC COPOLYMERS AS RHEOLOGICAL ADDITIVES IN DRILLING FLUIDS AND DRILLING FLUIDS COMPRISING SUCH COPOLYMERS

摘要

The invention relates to a drilling fluid in the form of a water-in-oil (W/O) emulsion comprising at least components (A) to (D), wherein component (D) is at least one (meth)acrylic copolymer, which contains at least one of structural units (D1), (D2) and (D3) to introduce at least one hydroxyl and/or amino functionality into the copolymer and which further contains at least one structural unit (D4), a use of said (meth)acrylic copolymer as rheological agent in drilling fluids, which are water-in-oil (W/O) emulsions, as well as to a method of producing oil and/or natural gas or of preparing the production thereof comprising the step of using the inventive drilling fluid for generating and/or operating a drill hole.