Copolymer surfactants for use in downhole fluids

Patent metadata

Field	Value
Publication number	US-10597571-B2
Application number	US-201816052451-A
Country	US
Kind code	B2
Filing date	Aug 1, 2018
Priority date	Nov 8, 2013
Publication date	Mar 24, 2020
Grant date	Mar 24, 2020

Abstract

Various embodiments disclosed relate to hydroxy-terminated poly(alkylene oxide) copolymer surfactants for use downhole, downhole compositions including the same, and methods of using the same. In various embodiments, the present invention provides a method of treating a subterranean formation. The method can include obtaining or providing a composition including a hydroxy-terminated poly(alkylene oxide) copolymer surfactant. The copolymer surfactant can include a first repeating unit having the structure —[R 1 O]—, wherein at each occurrence R 1 is independently a substituted or unsubstituted (C 2 -C 10 )alkylene group. The copolymer surfactant can include a second repeating unit having the structure —[R 2 O]—, wherein at each occurrence R 2 is independently a substituted or unsubstituted (C 2 -C 10 )alkylene group. The first repeating unit can have a lower molecular weight than the second repeating unit. The first repeating unit and the second repeating unit can have a random copolymer or block copolymer arrangement in the copolymer surfactant. The method can also include placing the composition in a subterranean formation downhole.

First claim

What is claimed is:

1. A method of treating a subterranean formation, the method comprising:
obtaining or providing a composition comprising a hydroxy-terminated poly(alkylene oxide) copolymer surfactant comprising
a first repeating unit, DP1; and
a second repeating unit, DP2;
wherein the copolymer surfactant has a Davies HLB of at least about 15, wherein the Davies HLB value is [number of OH groups in the copolymer surfactant]×1.5+[number of oxyethyl units in the copolymer surfactant]×0.33−[number of oxypropyl units in the copolymer surfactant]×0.15;
wherein the hydroxy-terminated poly(alkylene oxide) copolymer surfactant has the structure:

wherein the repeating units having subscripts DP2′ and DP2″ together are the second repeating unit, wherein DP2′ is 1, DP2″ is about 1 to about 910, and wherein DP1 is about 10 to about 2800; and

placing the composition in a subterranean formation downhole.

2. The method of claim 1 , wherein placing the composition in the subterranean formation comprises pumping the composition into a drill-string disposed in a wellbore, the drill-string comprising a drill bit at a downhole end of the drill-string.

3. The method of claim 1 , wherein the Davies HLB value of the hydroxy-terminated poly(alkylene oxide) copolymer surfactant is about 20 to about 100.

4. The method of claim 1 , wherein DP1 is about 20 to about 2,000.

5. The method of claim 1 , DP2″ is about 5 to about 800.

6. A method of treating a subterranean formation, the method comprising:
obtaining or providing a composition comprising a hydroxy-terminated poly(alkylene oxide) copolymer surfactant comprising:
a first repeating unit, DP1; and
a second repeating unit, DP2;
wherein the copolymer surfactant has a Davies HLB of about 20 to about 100, wherein the Davies HLB value is [number of OH groups in the copolymer surfactant]×1.5+[number of oxyethyl units in the copolymer surfactant]×0.33−[number of oxypropyl units in the copolymer surfactant]×0.15;
wherein the hydroxy-terminated poly(alkylene oxide) copolymer surfactant has the structure:

wherein the repeating units having subscripts DP2′ and DP2″ together are the second repeating unit, wherein DP2′ is 1, DP2″ is about 1 to about 910, and
wherein DP1 is about 10 to about 2800; and

placing the composition in a subterranean formation downhole.

Assignees

• Halliburton Energy Services Inc

Inventors

• Stone Shantel J
• Collins Ryan Patrick

Classifications

• C09K8/52

  Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning · CPC title

• C09K8/588

  characterised by the use of specific polymers {(polymeric surfactants C09K8/584)} · CPC title

• C09K8/68

  containing organic compounds · CPC title

• C09K8/12 Primary

  containing synthetic organic macromolecular compounds or their precursors · CPC title

• C08L71/02

  Polyalkylene oxides · CPC title