Cross-linked polyrotaxanes and their application in cement

Patent metadata

Field	Value
Publication number	US-11479708-B2
Application number	US-201916668730-A
Country	US
Kind code	B2
Filing date	Oct 30, 2019
Priority date	Oct 30, 2019
Publication date	Oct 25, 2022
Grant date	Oct 25, 2022

Abstract

This document relates to methods for preventing or inhibiting the formation of micro-cracks and fractures in the cement of an oil well using cement compositions that contain cross-linked polyrotaxane additives. The cement compositions containing the cross-linked polyrotaxane additives exhibit increased stiffness without suffering a decrease in compressive strength, as compared to the same cement without the cross-linked polyrotaxane additive.

First claim

What is claimed is:

1. A cement composition comprising:
cement; and
a cross-linked polyrotaxane additive comprising:
a polyrotaxane comprising a linear polymer and at least one ring compound, wherein the linear polymer is threaded through the opening of the ring compound; and
a cross-linker.

2. The composition of claim 1 , wherein the linear polymer is selected from the group consisting of a polyethylene glycol (PEG), a propylene glycol (PPG), a block copolymer of PEG and PPG, and a polysiloxane (PS).

3. The composition of claim 2 , wherein the linear polymer terminates with one or more of —NH 2 , —COOH, —OH, —CH 2 ═CH 2 , —COCH 2 (CH 3 )═CH 2 , —SH, —COCl, or a halide.

4. The composition of claim 3 , wherein the linear polymer is a PEG or a polysiloxane that terminates with one or more NH 2 groups.

5. The composition of claim 3 , wherein the linear polymer is a PEG or a polysiloxane that terminates with one or more —COOH groups.

6. The composition of claim 1 , wherein the linear polymer has a molecular weight of about 2000 g/mol to about 50000 g/mol, about 8000 g/mol to about 30,000 g/mol, or about 15,000 g/mol to about 25,000 g/mol.

7. The composition of claim 1 , wherein the linear polymer has a molecular weight of about 20,000 g/mol, about 25,000 g/mol, or about 28,000 g/mol.

8. The composition of claim 1 , wherein the ring compound is a cyclodextrin or cyclodextrin derivative.

9. The composition of claim 8 , wherein the cyclodextrin is selected from the group consisting of α-cyclodextrin (α-CD), β-cyclodextrin (β-CD), and γ-cyclodextrin (γ-CD) and combinations thereof.

10. The composition of claim 1 , wherein the amount of ring compound in the polyrotaxane is between about 20% to about 70%, about 50% to about 60%, or about 30% to about 40% by weight of the polyrotaxane.

11. The composition of claim 1 , wherein the polyrotaxane is selected from the group consisting of γ-CD-PS-NH 2 , γ-CD-PS-COOH, β-CD-PPG-NH 2 , and α-CD-PEG-NH 2 .

12. The composition of claim 1 , wherein the polyrotaxane comprises a stopper group at one or both ends of the linear polymer.

13. The composition of claim 12 , wherein the stopper group is selected from the group consisting of a dinitrofluorophenyl group, a cyclodextrin, a nitrophenol, and combinations thereof.

14. The composition of claim 13 , wherein the stopper group is p-nitrophenol (PNP) or 2,4-dinitrofluorobenzene (DNF).

15. The composition of claim 13 , wherein the polyrotaxane is α-CD-PEG-NH-DNF or γ-CD-PS-COOH-PNP.

16. The composition of claim 1 , wherein the cross-linker is selected from the group consisting of trimesoyl chloride, formaldehyde, cyanuric chloride (CC), and bisphenol A diglycidyl ether (DGE).

17. The composition of claim 1 , wherein the amount of cross-linker in the cross-linked polyrotaxane additive is between about 1% to about 10%, or about 2% to about 7%, or about 2% to about 4% by weight of the cross-linked polyrotaxane additive.

18. The composition of claim 17 , wherein the amount of cross-linker in the cross-linked polyrotaxane additive is about 3% by weight of the cross-linked polyrotaxane additive.

19. The composition of claim 1 , wherein the cross-linked polyrotaxane additive is selected from the group consisting of γ-CD-PS-NH-CC, γ-CD-PS-NH-DGE, γ-CD-PS-COO-DGE, α-CD-PEG-NH-P, and γ-CD-PS-COOH-P, wherein P is a polymer obtained from self-polymerization of the polyrotaxane.

20. The composition of claim 19 , wherein the cross-linked polyrotaxane additive is γ-CD-PS-COOH-P.

21. The composition of claim 1 , wherein the amount of cross-linked polyrotaxane additive in the cement composition is between about 0.1% to about 6%, about 1% to about 4%, or about 2% to about 3% by weight of the cement composition.

22. The composition of claim 21 , wherein the amount of cross-linked polyrotaxane additive in the cement composition is about 0.8% to about 1% by weight of the cement composition.

23. The composition of claim 1 , wherein the cement composition comprises one or more of a suspending agent or an anti-foaming agent.

24. The composition of claim 23 , wherein the one or more suspending agent or anti-foaming agent is hydroxyethylcellulose or a mixture of glycols, silicon-based compounds, and compounds with carboxylate functional groups.

25. The composition of claim 1 , wherein the cement composition further comprises water.

26. The composition of claim 25 , wherein the ratio of cement to water in the cement composition is about 50:50, about 60:40, or about 70:30 wt/v.

27. The composition of claim 1 , wherein the cement composition has a Young's modulus of about 0.1 GPa to about 40 GPa, about 3 GPa to about 25 GPa, or about 5 GPa to about 20 GPa at a pressure of about 0.1 MPa to about 150 MPa, about 10 MPa to about 100 MPa, or about 20 MPa to about 40 MPa, at a temperature of about 77° F. to about 450° F., about 125° F. to about 350° F., or about 150° F. to about 200° F.

28. The composition of claim 27 , wherein the cement composition has a Young's modulus of about 5 GPa to about 10 GPa at a pressure of about 20 MPa and a temperature of about 180° F.

29. The composition of claim 1 , wherein the cement composition has a compressive strength of about 1000 psi to about 10,000 psi, about 2000 psi to about 8000 psi, or about 3500 psi to about 6500 psi, at a pressure of about 0.1 MPa to about 150 MPa, about 10 MPa to about 100 MPa, or about 20 MPa to about 40 MPa, at a temperature of about 77° F. to about 450° F., about 125° F. to about 350° F., or about 150° F. to about 200° F.

30. The composition of claim 29 , wherein the cement composition has a compressive strength of about 4500 psi to about 5500 psi at a pressure of about 20 MPa and a temperature of about 180° F.

31. The composition of claim 1 , wherein the cement composition exhibits improved stiffness as compared to the same composition without the cross-linked polyrotaxane additive.

32. A method of preparing a cement composition, comprising:
a) reacting a polyrotaxane comprising a linear polymer and at least one ring compound, wherein the linear polymer is threaded through the opening of the ring compound, with a cross-linker to form a cross-linked polyrotaxane additive; and
b) mixing the cross-linked polyrotaxane additive with cement.

33. The method of claim 32 , wherein the linear polymer is selected from the group consisting of a polyethylene glycol (PEG), a propylene glycol (PPG), a block copolymer of PEG and PPG, and a polysiloxane (PS).

34. The method of claim 33 , wherein the linear polymer terminates with one or more of —NH 2 , —COOH, —OH, —CH 2 ═CH 2 , —COCH 2 (CH 3 )═CH 2 , —SH, —COCl, or a halide.

35. The method of claim 32 , wherein the linear polymer has a molecular weight of about 2000 g/mol to about 50000 g/mol, about 8000 g/mol to about 30,000 g/mol, or about 15,000 g/mol to about 25,000 g/mol.

36. The method of claim 32 , wherein the ring compound is a cyclodextrin or cyclodextrin derivative.

37. The method of claim 36 , wherein the cyclodextrin is selected from the group consisting of α-cyclodextrin (α-CD), β-cyclodextrin (β-CD), and γ-cyclodextrin (γ-CD) and combinations thereof.

38. The method of claim 32 , wherein the amount of ri

Assignees

• Saudi Arabian Oil Co

Inventors

• Patel Hasmukh A
• Boul Peter
• Thaemlitz Carl

Classifications

• C04B22/16

  containing phosphorus in the anion, e.g. phosphates · CPC title

• C04B24/2641

  Polyacrylates; Polymethacrylates · CPC title

• C04B24/32

  Polyethers, e.g. alkylphenol polyglycolether · CPC title

• C08G83/007

  Polyrotaxanes; Polycatenanes · CPC title

• C04B24/40

  Compounds containing silicon, titanium or zirconium {or other organo-metallic compounds; Organo-clays; Organo-inorganic complexes} · CPC title