Salt-tolerant, fast-dissolving, water-soluble rheology modifiers
Compounds, compositions and methods of use thereof are provided, the compounds comprising a hydrophobically modified polyelectrolyte comprising a nonionic monomer, an ionic monomer, a monomer having the structure of Formula 1, and a monomer having the structure of Formula 2, wherein R 1 , R 2 , R 3 , R 5 , R 6 , and R 7 are independently hydrogen, unsubstituted alkyl, substituted alkyl, carbonyl, carboxyl, aryl, or alkaryl; R 4 is linear C 3 to C 30 alkyl; R 8 is branched C 3 to C 30 alkyl; X 1 and X 2 are independently —C(O)O—, —C(O)NR 9 —, —O—, —C(R 9 ) 2 O—, -arylene-, -arylene-C(R 9 ) 2 O—, -arylene-C(R 9 ) 2 N(R 10 )— or -arylene-C(R 9 ) 2 N + (R 10 ) 2 —; R 9 and R 10 is independently hydrogen or a C 1 to C 4 alkyl; and wherein a molar ratio of the monomer of Formula 1 to the monomer of Formula 2 is from about 1.5:1 to about 15:1. The compounds are useful as viscosifying agents in oil and gas applications.
1. A hydrophobically modified polyelectrolyte comprising a nonionic monomer, an anionic monomer, a monomer having the structure of Formula 1, and a monomer having the structure of Formula 2,
wherein
R 1 , R 2 , R 3 , R 5 , R 6 , and R 7 are independently hydrogen, unsubstituted alkyl, substituted alkyl, carbonyl, carboxyl, aryl, or alkaryl;
R 4 is linear C 3 to C 30 alkyl;
R 8 is branched C 3 to C 30 alkyl;
X 1 and X 2 are independently —C(O)O—, —C(O)NR 9 —, —O—, —C(R 9 ) 2 O—, arylene, arylene-C(R 9 ) 2 O—, arylene-C(R 9 ) 2 N(R 10 )—, arylene-C(R 9 ) 2 N + (R 10 ) 2 —; and
R 9 and R 10 is hydrogen or C 1 to C 4 alkyl;
wherein a molar ratio of the monomer of Formula 1 to the monomer of Formula 2 is from about 4:1 to about 15:1.
2. The polyelectrolyte of claim 1 , wherein the anionic monomer comprises 2-acrylamido-2-methyl-1-propanesulfonic acid, acrylic acid, methacrylic acid, 4-vinylbenzenesulfonic acid, a salt thereof, or a mixture thereof.
3. The polyelectrolyte of claim 2 , wherein the anionic monomer comprises 2-acrylamido-2-methyl-1-propanesulfonic acid, or a salt thereof.
4. The polyelectrolyte of claim 1 , wherein the nonionic monomer comprises acrylamide, N,N-dimethylacrylamide, N-vinylpyrrolidone, vinyl acetate, or a combination thereof.
5. The polyelectrolyte of claim 3 , wherein the nonionic monomer comprises acrylamide.
6. The polyelectrolyte of claim 1 , wherein the molar ratio of the monomer of Formula 1 to the monomer of Formula 2 is from about 4:1 to about 12:1.
7. The polyelectrolyte of claim 4 , wherein the molar ratio of the monomer of Formula 1 to the monomer of Formula 2 is from about 4:1 to about 10:1.
8. The polyelectrolyte of claim 5 , wherein the molar ratio of the monomer of Formula 1 to the monomer of Formula 2 is from about 6:1 to about 8:1.
9. The polyelectrolyte of claim 1 , wherein R 1 , R 2 , R 3 , R 5 , R 6 , and R 7 are independently hydrogen or C 1 to C 4 alkyl.
10. The polyelectrolyte of claim 8 , wherein R 3 and R 7 are hydrogen or methyl and R 1 , R 2 , R 5 , and R 6 are hydrogen.
11. The polyelectrolyte of claim 10 , wherein R 4 is linear C 8 to C 20 alkyl and R 8 is branched C 8 to C 20 alkyl.
12. The polyelectrolyte of claim 1 , wherein R 4 is linear C 10 to C 16 alkyl.
13. The polyelectrolyte of claim 12 , wherein R 8 is branched C 10 to C 18 alkyl.
14. The polyelectrolyte of claim 1 , wherein R 8 is branched C 10 to C 15 alkyl.
15. The polyelectrolyte of claim 1 , wherein R 9 is hydrogen and R 10 is C 1 to C 4 alkyl.
16. The polyelectrolyte of claim 1 , wherein X 1 and X 2 are —C(O)O—.
17. A composition comprising the polyelectrolyte of claim 1 in powder or granular form and a surfactant.
18. A method of increasing the viscosity of an aqueous solution comprising contacting the polyelectrolyte of claim 1 with the aqueous solution, thereby increasing the viscosity of the aqueous solution.
19. A hydrophobically modified polyelectrolyte comprising a nonionic monomer, an ionic monomer, lauryl acrylate, and isotridecyl acrylate.