Polycarbonate block copolymers

1. A polymer composition comprising a block copolymer having a 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;

wherein the polymer composition has a PDI of less than 2.

2. The polymer composition of claim 1 , wherein X is selected from the group consisting of: halogen, azide, nitrile, and —OR z .

3. The polymer composition of claim 1 , 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.

4. The polymer composition of claim 3 , wherein the block copolymer has the formula:

wherein X′ is selected from the group consisting of —OH and —OR z .

5. The polymer composition of claim 3 , wherein R 100 is a methyl group.

6. The polymer composition of claim 3 , 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.

7. The polymer composition of claim 1 , wherein X is —OH.

8. The polymer composition of claim 1 , wherein —B is selected from the group consisting of: polyethers, polyolefin bearing hydrophilic functional groups, polypeptides, polysaccharides and polyamines.

9. The polymer composition of claim 8 , wherein —B is a polyether.

10. The polymer composition of claim 1 , 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 .

11. The polymer composition of claim 10 , wherein the copolymer is selected from the group consisting of:

12. The polymer composition of claim 10 , wherein —Z— is —CH 2 CH 2 —.

13. The polymer composition of claim 10 , wherein —Z— is —CH(CH 3 )CH 2 —.

14. The polymer composition of claim 10 , 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 .

15. The polymer composition of claim 10 , wherein the block copolymer comprises poly(propylene carbonate) and poly(ethylene glycol).

16. The polymer composition of claim 10 , wherein the block copolymer is selected from the group consisting of:

17. A polymer composition comprising 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;

wherein the polymer composition has a PDI of less than 2.

18. The polymer composition of claim 17 , wherein at least one X′ is —OR z .

19. The polymer composition of claim 17 , wherein the copolymer is selected from the group consisting of:

20. A polymer composition comprising a triblock 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, and wherein the polymer composition has a PDI of less than 2.

21. The polymer composition of claim 20 , wherein-B is a polyether.

22. The polymer composition of claim 20 , wherein -A- is poly(propylene carbonate).

23. The polymer composition of claim 20 , wherein -A- is poly(ethylene carbonate).

24. The polymer composition of claim 21 , 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.

25. The polymer composition of claim 24 , wherein the triblock copolymer has a formula:

26. The polymer composition of claim 25 , 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.

27. The polymer composition of claim 25 , wherein Y is —H.

28. The polymer composition of claim 26 , wherein R 100 is absent.

29. The polymer composition of claim 26 , wherein R 100 is methyl.

30. The polymer composition of claim 26 , wherein R 100 comprises a random mixture of methyl and one or more C 3-30 alkyl groups.

31. The polymer composition of claim 24 , 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.

32. The polymer composition of claim 24 , 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.

33. The polymer composition of claim 20 , wherein the PDI is less than 1.4, less than 1.2 or less than about 1.1.

34. The polymer composition of claim 20 , wherein -A- contains greater than about 95% carbonate linkages.

35. The polymer composition of claim 21 , 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.

36. The polymer composition of claim 35 , wherein R 100 is absent.

37. The polymer composition of claim 35 , wherein R 100 is methyl.

38. The polymer composition of claim 21 , 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.

39. The polymer composition of claim 38 , wherein R 100 is absent.

40. The polymer composition of claim 38 , wherein R 100 is methyl.