Ionic polymer compositions

1. An orthopedic implant comprising a crosslinked ionic polymer that comprises sulfonic-acid-derivatized groups, wherein the sulfonic-acid-derivatized groups are present at a surface of the crosslinked ionic polymer and extend from the surface into a bulk of the crosslinked ionic polymer by a distance of at least 500 microns, and the crosslinked ionic polymer has a thickness of up to 10 mm.

2. The orthopedic implant of claim 1 , wherein the sulfonic-acid-derivatized groups are amino-sulfonic-acid-derivatized groups.

3. The orthopedic implant of claim 2 , wherein the crosslinked ionic polymer comprises a measurable amount of an amino sulfonic acid compound of the formula (H 2 N) x R(SO 3 H) y or a salt thereof, where R is an organic moiety, x is a positive integer and y is a positive integer.

4. The orthopedic implant of claim 3 , wherein R is a hydrocarbon moiety.

5. The orthopedic implant of claim 4 , wherein the hydrocarbon moiety is an alkane moiety, an alkene moiety, an alkyne moiety, an aromatic moiety, or a hydrocarbon moiety having a combination of two or more of alkane, alkene, alkyne and aromatic substituents.

6. The orthopedic implant of claim 4 , wherein the hydrocarbon moiety is a C 1 -C 12 hydrocarbon moiety.

7. The orthopedic implant of claim 2 , wherein the crosslinked ionic polymer comprises a measurable amount of an amino sulfonic acid compound selected from taurine and taurine derivatives.

8. The orthopedic implant of claim 1 , wherein the sulfonic-acid-derivatized groups are sulfonic-acid-derivatized carboxylic groups.

9. The orthopedic implant of claim 8 , wherein the crosslinked ionic polymer further comprises underivatized carboxylic acid groups.

10. The orthopedic implant of claim 9 , wherein the underivatized carboxylic acid groups correspond to one or more of the following: underivatized acrylic acid polymerized monomers within the ionic polymer, underivatized methacrylic acid polymerized monomers within the ionic polymer, underivatized crotonic acid polymerized monomers within the ionic polymer, underivatized linolenic acid polymerized monomers within the ionic polymer, underivatized maleic acid polymerized monomers within the ionic polymer, and underivatized fumaric acid polymerized monomers within the ionic polymer, and wherein the amino-sulfonic-acid-derivatized carboxylic acid groups correspond to one or more of amino sulfonic-acid-derivatized acrylic acid polymerized monomers within the ionic polymer, amino-sulfonic-acid-derivatized methacrylic acid polymerized monomers within the ionic polymer, amino-sulfonic-acid-derivatized crotonic acid polymerized monomers within the ionic polymer, amino-sulfonic-acid-derivatized linolenic acid polymerized monomers within the ionic polymer, amino-sulfonic-acid-derivatized maleic acid polymerized monomers within the ionic polymer, and amino-sulfonic-acid-derivatized fumaric acid polymerized monomers within the ionic polymer.

11. The orthopedic implant of claim 1 , wherein the crosslinked ionic polymer comprises a gradient in a concentration of the sulfonic-acid-derivatized groups.

12. The orthopedic implant of claim 1 , wherein the sulfonic-acid-derivatized groups extend into the bulk of the crosslinked ionic polymer by a distance of at least 1 mm.

13. The orthopedic implant of claim 1 , wherein the sulfonic-acid-derivatized groups are present throughout greater than 20% of the thickness of the crosslinked ionic polymer.

14. The orthopedic implant of claim 1 , wherein the sulfonic-acid-derivatized groups are present throughout greater than 50% of the thickness of the crosslinked ionic polymer.

15. The orthopedic implant of claim 1 , wherein the sulfonic-acid-derivatized groups are present throughout greater than 75% of the thickness of the crosslinked ionic polymer.

16. The orthopedic implant of claim 1 , wherein the sulfonic-acid-derivatized groups are present throughout 100% of the thickness of the crosslinked ionic polymer.

17. The orthopedic implant of claim 1 , wherein a concentration of the sulfonic-acid-derivatized groups decreases by at least 10% from the point on the surface of the crosslinked ionic polymer and at least one point in the bulk of the crosslinked ionic polymer.

18. The orthopedic implant of claim 1 , wherein a concentration of the sulfonic-acid-derivatized groups does not vary by more than +/−10% between any two points in the crosslinked ionic polymer.

19. The orthopedic implant of claim 9 , wherein a concentration of the sulfonic-acid-derivatized carboxylic acid groups and a concentration of the underivatized carboxylic acid groups do not vary by more than +/−10% between any two points in the crosslinked ionic polymer.

20. The orthopedic implant of claim 9 , wherein the crosslinked ionic polymer comprises a gradient in a concentration of the sulfonic-acid-derivatized carboxylic acid groups and a gradient in a concentration of the underivatized carboxylic acid groups.

21. The orthopedic implant of claim 9 , wherein a concentration of the sulfonic-acid-derivatized carboxylic acid groups decreases by at least 10% from the point on the surface of the crosslinked ionic polymer and at least one point in the bulk of the crosslinked ionic polymer, and wherein a concentration of the underivatized carboxylic acid groups increases by at least 10% from the point on the surface of the crosslinked ionic polymer and at least one point in the bulk of the crosslinked ionic polymer.

22. The orthopedic implant of claim 9 , wherein a molar ratio of the sulfonic-acid-derivatized carboxylic acid groups to the underivatized carboxylic acid groups decreases by at least 10% from the point on the surface of the crosslinked ionic polymer and at least one point in the bulk of the crosslinked ionic polymer.

23. The orthopedic implant of claim 1 , wherein the implant comprises an interpenetrating or semi-interpenetrating polymer network that comprises a first polymeric network comprising a first polymer and a second polymeric network comprising the ionic polymer.

24. The orthopedic implant of claim 23 , wherein the first polymer is a hydrophobic polymer.

25. The orthopedic implant of claim 23 , wherein the first polymer is a thermoplastic polymer.

26. The orthopedic implant of claim 23 , wherein the first polymer is a polyurethane.

27. The orthopedic implant of claim 23 , wherein the interpenetrating or semi-interpenetrating polymer network has first and second surfaces, wherein the first surface has a composition corresponding to the first polymer and wherein a concentration of the sulfonic-acid-derivatized groups is at a maximum at the second surface and decreases to zero or substantially zero concentration within the bulk of the interpenetrating or semi-interpenetrating polymer network.

28. The orthopedic implant of claim 1 , wherein the implant is configured to repair or replace cartilage in a joint in the body.

29. The orthopedic implant of claim 28 , wherein the joint in the body is selected from a knee joint, a condyle, a patella, a tibial plateau, an ankle joint, an elbow joint, a shoulder joint, a finger joint, a thumb joint, a glenoid, a hip joint, an intervertebral disc, an intervertebral facet joint, a labrum, a meniscus, a metacarpal joint, a metatarsal joint, a toe joint, a temporomandibular joint, and a wrist joint, including portions thereof.

30. An interpenetrating or semi-interpenetrating polymer network that comprises a first polymeric network comprising a first polymer and a second polymeric network comprising a crosslinked ionic polymer that comprises sulfonic-acid-derivatized groups, wherein the sulfonic-acid-derivatized groups are present at a surface of the interpenetrating or semi-interpenetrating polymer network and extend into the interpenetrating or semi-interpenetrating polymer network by a distance of at least 500 microns, and the interpenetrating or semi-interpenetrating polymer network has a thickness of up to 10 mm.

31. The interpenetrating or semi-interpenetrating polymer network of claim 30 , wherein the sulfonic-acid-derivatized groups are amino-sulfonic-acid-derivatized groups.

32. The interpenetrating or semi-interpenetrating polymer network of claim 30 , wherein the sulfonic-acid-derivatized groups are sulfonic-acid-derivatized carboxylic groups.

33. The interpenetrating or semi-interpenetrating polymer network of claim 30 , wherein the crosslinked ionic polymer further comprises underivatized carboxylic acid groups.

34. The interpenetrating or semi-interpenetrating polymer network of any of claim 30 , wherein the first polymer is hydrophobic polymer.

35. The interpenetrating or semi-interpenetrating polymer network of claim 30 , wherein the first polymer is a thermoplastic polymer.

36. The interpenetrating or semi-interpenetrating polymer network of claim 30 , wherein the first polymer is a polyurethane.

37. The interpenetrating or semi-interpenetrating polymer network of claim 36 , wherein the polyurethane is a polyether urethane.

38. The interpenetrating or semi-interpenetrating polymer network of claim 30 , having first and second surfaces, wherein the first surface has a composition corresponding to the first polymer and wherein a concentration of the sulfonic-acid-derivatized groups is at a maximum at the second surface and decreases to zero or substantially zero concentration within the bulk of the interpenetrating or semi-interpenetrating polymer network.

39. The interpenetrating or semi-interpenetrating polymer network of claim 34 , wherein the hydrophobic polymer is a polyurethane and wherein at least a portion of the underivatized carboxylic acid groups correspond to underivatized acrylic acid polymerized monomers within the ionic polymer.

40. The interpenetrating or semi-interpenetrating polymer network of claim 30 , wherein the sulfonic-acid-derivatized groups are present throughout greater than 20% of the thickness of the interpenetrating or semi-interpenetrating polymer network.

41. The interpenetrating or semi-interpenetrating polymer network of claim 30 , wherein the sulfonic-acid-derivatized groups are present throughout greater than 50% of the thickness of the interpenetrating or semi-interpenetrating polymer network.

42. The interpenetrating or semi-interpenetrating polymer network of claim 30 , wherein the sulfonic-acid-derivatized groups are present throughout greater than 75% of the thickness of the interpenetrating or semi-interpenetrating polymer network.

43. The interpenetrating or semi-interpenetrating polymer network of claim 30 , wherein the sulfonic-acid-derivatized groups are present throughout 100% of the thickness of the interpenetrating or semi-interpenetrating polymer network.