| abstract |
Use of a chemically derivatized polysaccharide-protein blend comprising partially water-swellable polysaccharides and proteins, wherein the polysaccharides and proteins have each been at least partially chemically covalently modified by a) at least one noncrosslinking derivatization; and b) at least one crosslinking derivatization, wherein the polysaccharides and proteins have been at least partially chemically covalently crosslinked with one another, and wherein the chemically derivatized polysaccharide-protein blend in aqueous medium forms a hydrogel, as an additive for drilling muds - in the development, completion and exploitation of underground mineral oil and natural gas deposits, and in deep wells. |