US 12,454,638 B2
Drilling fluids including a viscosifier, and related methods
Kristina Daeffler, Sugar Land, TX (US); Linus Sebelin, Houston, TX (US); and Balakrishnan Panamarathupalayam, Houston, TX (US)
Assigned to Schlumberger Technology Corporation, Sugar Land, TX (US)
Filed by Schlumberger Technology Corporation, Sugar Land, TX (US)
Filed on Nov. 30, 2023, as Appl. No. 18/525,132.
Prior Publication US 2025/0179342 A1, Jun. 5, 2025
Int. Cl. C09K 8/24 (2006.01); E21B 21/00 (2006.01)
CPC C09K 8/24 (2013.01) [E21B 21/003 (2013.01)] 20 Claims
OG exemplary drawing
 
12. A method of operating a wellbore, the method comprising:
pumping a drilling fluid into a wellbore extending through an earth formation, the drilling fluid comprising:
a base fluid; and
a viscosifier comprising:
a first component comprising a reaction product of at least one acrylamide monomer and at least one sulfonated anionic monomer; and
a second component comprising styrene-butadiene rubber; and
operating a drill bit while pumping the drilling fluid in the wellbore; wherein the first component further comprises a branching agent; wherein the branching agent may constitute from about 0.1 weight percent to about 5.0 weight percent of the first component.