US 12,441,934 B2
Viscosifying friction reducers
Genyao Lin, The Woodlands, TX (US); Louis Villafane, Pittsburgh, PA (US); Kailas Sawant, Mars, PA (US); Kevin Frederick, Evans City, PA (US); and Shih-Ruey Chen, Studio City, CA (US)
Assigned to Energy Solutions (US) LLC, The Woodlands, TX (US)
Filed by ENERGY SOLUTIONS (US) LLC, The Woodlands, TX (US)
Filed on Sep. 22, 2023, as Appl. No. 18/371,726.
Application 18/371,726 is a division of application No. 17/007,284, filed on Aug. 31, 2020, granted, now 11,795,376.
Application 17/007,284 is a continuation of application No. 15/050,824, filed on Feb. 23, 2016, abandoned.
Claims priority of provisional application 62/126,170, filed on Feb. 27, 2015.
Prior Publication US 2024/0018412 A1, Jan. 18, 2024
Int. Cl. C09K 8/64 (2006.01); C09K 8/36 (2006.01); C09K 8/68 (2006.01); C09K 8/72 (2006.01); C09K 8/82 (2006.01); E21B 43/26 (2006.01)
CPC C09K 8/64 (2013.01) [C09K 8/36 (2013.01); C09K 8/68 (2013.01); C09K 8/725 (2013.01); C09K 8/82 (2013.01); E21B 43/26 (2013.01); C09K 2208/14 (2013.01); C09K 2208/28 (2013.01)] 11 Claims
 
1. A water-in-oil emulsion comprising an oil phase (O) and an aqueous phase (A) at an O/A ratio of from about 1:8 to about 10:1;
wherein the water-in-oil emulsion includes the oil phase as a continuous phase comprising an inert hydrophobic liquid, at least one water-insoluble hydrophobic monomer, and at least one surfactant, and
the aqueous phase as a dispersed phase of distinct particles in the oil phase comprising water and a water soluble polymer comprising: (i) at least one acrylamide monomer and (ii) at least one acrylic acid monomer;
wherein the water soluble polymer is present in an amount from about 10 to about 35 weight percent of the water-in-oil emulsion;
wherein the aqueous phase is present in an amount of from 60 to 85% by weight based on the weight of the water-in-oil emulsion;
wherein the inert hydrophobic liquid is present in an amount of from 20 to 80% by weight based on the weight of the water-in-oil emulsion;
wherein the acrylamide monomer is present in an amount of 50 to 90% by weight based on the weight of the monomers in the water soluble polymer;
wherein the acrylic acid monomer is present in an amount of 10 to 40% by weight based on the weight of the monomers in the water soluble polymer.