| abstract |
Use of a chemically derivatized polysaccharide-protein blend containing partially water-swellable polysaccharides and proteins, wherein the polysaccharides and proteins are each at least partially chemically covalently modified by a) at least one non-crosslinking derivatization; and b) at least one crosslinking derivatization, wherein the polysaccharides and proteins are at least partially cross-linked chemically covalently, and wherein the chemically derivatized polysaccharide-protein blend forms a hydrogel in an aqueous medium, as an additive for drilling fluids - in the development, completion and exploitation underground oil and gas wells and deep wells. |