Polycarbonate block copolymers
The disclosure pertains to amphiphilic block copolymers comprising an aliphatic polycarbonate chain coupled to a hydrophilic polymer. Such amphiphilic polymers may have the formula A-L-B, where A- is a polycarbonate or polyethercarbonate chain having from about 3 to about 500 repeating units, L is a linker moiety and -B is a hydrophilic oligomer having from about 4 to about 200 repeating units. Provided copolymers are useful as surfactants capable of emulsifying aqueous solutions and supercritical carbon dioxide. Provided copolymers also have utility as additives for use in enhanced oil recovery methods.
1. A method of enhancing product recovery from oil wells by introducing a solution comprising a block copolymer, A-L-B, to an oil containing geological formation, wherein:
A is a polycarbonate or polyether carbonate chain having from about 3 to about 500 repeating units;
L is a bond or polyfunctional moiety; and
B is a hydrophilic oligomer having from about 4 to about 500 repeating units.
2. The method of claim 1 comprising the step of pumping the solution comprising a block copolymer into an oil well.
3. The method of claim 1 , wherein the solution comprising a block copolymer is introduced in combination with supercritical CO 2 .
4. The method of claim 3 , wherein the supercritical CO 2 is combined with water or brine to form an emulsion capable of flushing trapped oil from the geological formation.
5. The method of claim 1 , wherein the block copolymer, A-L-B is represented by structural formula:
where X is selected from the group consisting of: halogen, —OH, azide, nitrile, and —OR z ;
each R a , R b , R c , and R d is independently selected from the group consisting of: hydrogen, halogen, —CH 2 OR z , optionally substituted C 1-10 aliphatic, optionally substituted 6- to 14-membered aromatic, optionally substituted 3- to 14-membered heterocyclic, and optionally substituted 5- to 14-membered heteroaryl, and where any two or more of R a , R b , R c , and R d may be taken together to form an optionally substituted 3- to 12-membered ring, optionally containing one or more heteroatoms;
L is a bond or a polyfunctional moiety;
B is a hydrophilic oligomer having from about 4 to about 100 repeating units;
n is an integer between 4 and 100;
R z is selected from the group consisting of R 10 , —C(O)R 10 , —SO 2 R 10 , —Si(R 10 ) 3 , —C(O)N(R 10 ) 2 ; and
R 10 is an optionally substituted moiety selected from the group consisting of: C 1-20 aliphatic; C 1-12 heteroaliphatic; 6- to 14-membered aryl; and 5- to 14-membered heteroaryl.
6. The method of claim 5 , wherein X is selected from the group consisting of: halogen, azide, nitrile, and —OR z .
7. The method of claim 5 , wherein the block copolymer has the formula:
wherein, R 100 is optionally present, and if present is selected from the group consisting of —CH 3 , —CF 3 , —CH 2 CH 3 , —CH 2 OR z , and —CH 2 Cl.
8. The method of claim 7 , wherein the block copolymer has the formula:
wherein X′ is selected from the group consisting of —OH and —OR z .
9. The method of claim 7 , wherein R 100 is a methyl group.
10. The method of claim 7 , wherein R 100 is a random mixture of methyl groups and one or more moieties selected from group consisting of ethyl, trifluoromethyl, chloromethyl, —CH 2 OR z and a C 6-30 alkyl group.
11. The method of claim 5 , wherein X is —OH.
12. The method of claim 5 , wherein -B is selected from the group consisting of: polyethers, polyolefin bearing hydrophilic functional groups, polypeptides, polysaccharides and polyamines.
13. The method of claim 12 , wherein -B is a polyether.
14. The method of claim 5 , wherein the block copolymer has the formula:
wherein, m is an integer between 5 and 200;
R 100 is optionally present, and if present is selected from the group consisting of —CH 3 , —CF 3 , —CH 2 CH 3 , —CH 2 OR z , and —CH 2 Cl;
—Z— is an optionally substituted C 1-6 aliphatic group; and
—Y is selected from the group consisting of —H and R z .
15. The method of claim 14 , wherein the copolymer is selected from the group consisting of:
16. The method of claim 14 , wherein —Z— is —CH 2 CH 2 —.
17. The method of claim 14 , wherein —Z— is —CH(CH 3 )CH 2 —.
18. The method of claim 14 , wherein the copolymer has the formula:
wherein X′, is —OH or —OR z , and
Y′ is selected from the group consisting of optionally substituted C 1-8 aliphatic, a silyl protecting group, —H, and —C(O)R 10 .
19. The method of claim 14 , wherein the block copolymer comprises poly(propylene carbonate) and poly(ethylene glycol).
20. The method of claim 18 , wherein the block copolymer is selected from the group consisting of:
21. The method of claim 1 , wherein the solution comprises a block copolymer having a formula:
wherein
X′ is selected from the group consisting of —OH and —OR z ;
R 100 is optionally present, and if present is selected from the group consisting of —CH 3 , —CF 3 , —CH 2 CH 3 , —CH 2 OR z , and —CH 2 Cl;
each n is independently an integer between 4 and 100;
—Z— is an optionally substituted C 1-6 aliphatic group;
m is an integer between 5 and 200;
R z is selected from the group consisting of R 10 , —C(O)R 10 , —SO 2 R 10 , —Si(R 10 ) 3 , —C(O)N(R 10 ) 2 ; and
R 10 is at each occurrence an optionally substituted moiety independently selected from the group consisting of: C 1-12 aliphatic; C 1-12 heteroaliphatic; 6- to 14-membered aryl; and 5- to 14-membered heteroaryl.
22. The method of claim 21 , wherein at least one X′ is —OR z .
23. The method of claim 21 , wherein the copolymer is selected from the group consisting of:
24. The method of claim 1 , wherein the solution comprises a block copolymer having the formula B-A-B, wherein -A- is a polycarbonate chain having from about 3 to about 500 repeating units and each B is independently a hydrophilic oligomer having from about 4 to about 200 repeating units, wherein B is selected from the group consisting of: polyethers, polyolefin bearing hydrophilic functional groups, polypeptides, polysaccharides, and polyamines.
25. The method of claim 24 , wherein -B is a polyether.
26. The method of claim 24 , wherein -A- is poly(propylene carbonate).
27. The method of claim 24 , wherein -A- is poly(ethylene carbonate).
28. The method of claim 25 , wherein the triblock copolymer has a formula:
wherein
—Z— is an optionally substituted C 1-6 aliphatic group,
—Y is selected from the group consisting of —H and R z ;
each R a , R b , R c , and R d is independently selected from the group consisting of: hydrogen, halogen, —CH 2 OR z , optionally substituted C 1-10 aliphatic, optionally substituted 6- to 14-membered aromatic, optionally substituted 3- to 14-membered heterocyclic, and optionally substituted 5- to 14-membered heteroaryl, and wherein any two or more of R a , R b , R c , and R d may be taken together to form an optionally substituted 3- to 12-membered ring, optionally containing one or more heteroatoms,
each L is independently a bond or a polyfunctional moiety,
n is an integer between 4 and 100,
m is an integer between about 4 and about 500,
m′ is, on average approximately equal to m,
R z is selected from the group consisting of R 10 , —C(O)R 10 , —SO 2 R 10 , —Si(R 10 ) 3 , —C(O)N(R 10 ) 2 , and
R 10 is an optionally substituted moiety selected from the group consisting of: C 1-20 aliphatic; C 1-12 heteroaliphatic; 6- to 14-membered aryl; and 5- to 14-membered heteroaryl.
29. The method of claim 28 , wherein the triblock copolymer has a formula:
30. The method of claim 29 , wherein the copolymer has a formula:
wherein R 100 is optionally present, and if present is selected from the group consisting of —CH 3 , —CF 3 , —CH 2 CH 3 , —CH 2 OR z , —CH 2 Cl, a C 3-30 alkyl group, and mixtures of two or more of these.
31. The method of claim 29 , wherein Y is —H.
32. The method of claim 30 , wherein R 100 is absent.
33. The method of claim 30 , wherein R 100 is methyl.
34. The method of claim 30 , wherein R 100 comprises a random mixture of methyl and one or more C3-30 alkyl groups.
35. The method of claim 28 , wherein the value of n is selected from the group consisting of:
between about 3 and about 50;
between about 3 and about 25;
between about 10 and about 20; and
between about 3 and about 10.
36. The method of claim 28 , wherein the value of m is selected from the group consisting of:
between about 5 and about 200;
between about 5 and about 50;
between about 5 and about 25;
between about 10 and about 20; and
between about 5 and about 10.
37. The method of claim 24 , wherein -A- contains greater than about 95% carbonate linkages.
38. The method of claim 24 , wherein the triblock copolymer has the formula:
wherein
n is an integer between 4 and 100,
m is an integer between about 4 and about 500,
m′ is, on average approximately equal to m;
R 100 is optionally present, and if present is selected from the group consisting of —CH 3 , —CF 3 , —CH 2 CH 3 , —CH 2 OR z , and —CH 2 Cl;
each R z is independently R 10 , —C(O)R 10 , —SO 2 R 10 , —Si(R 10 ) 3 , or —C(O)N(R 10 ) 2 ; and
each R 10 is independently optionally substituted C 1-20 aliphatic, optionally substituted C 1-12 heteroaliphatic, optionally substituted 6- to 14-membered aryl, or optionally substituted 5- to 14-membered heteroaryl.
39. The method of claim 38 , wherein R 100 is absent.
40. The method of claim 38 , wherein R 100 is methyl.
41. The method of claim 24 , wherein the triblock copolymer has the formula:
wherein
n is an integer between 4 and 100,
m is an integer between about 4 and about 500,
m′ is, on average approximately equal to m; and
R 100 is optionally present, and if present is selected from the group consisting of —CH 3 , —CF 3 , —CH 2 CH 3 , —CH 2 OR z , and —CH 2 Cl;
each R z is independently R 10 , —C(O)R 10 , —SO 2 R 10 , —Si(R 10 ) 3 , or —C(O)N(R 10 ) 2 ; and
each R 10 is independently optionally substituted C 1-20 aliphatic, optionally substituted C 1-12 heteroaliphatic, optionally substituted 6- to 14-membered aryl, or optionally substituted 5- to 14-membered heteroaryl.
42. The method of claim 41 , wherein R 100 is absent.
43. The method of claim 41 , wherein R 100 is methyl.