Urethane-crosslinked biodegradable elastomers

1. An implantable biodegradable elastomeric cross-linked polyester material comprising:

a plurality of A and B components, wherein the A and B components form a plurality of polymeric backbones formed of (-A-B-) repeat units, having the general formula (-A-B-) p , wherein:

p is an integer greater than 1;

the (-A-B-) repeat units have a chemical structure produced by condensation of a polyol component A′ with a polyacid component B′; and

one or more agents selected from the group consisting of therapeutic agents, diagnostic agents, prophylactic agents, nutraceutical agents, and combinations thereof;

wherein the A component of at least two of the (-A-B-) repeat units within each of the polymeric backbones has at least one free hydroxyl group present thereon, prior to crosslinking;

wherein crosslinking is carried out by a polyisocyanate crosslinker and the at least one free hydroxyl group to the polyisocyanate crosslinker is at a molar ratio of between about 1:0.2 and about 1:0.8 or between about 1:1.2 and about 1:1.5; and

wherein urethane cross-links covalently crosslink the polymeric backbones between the A components of the at least two (-A-B-) repeat units within each of the polymeric backbones.

2. The implantable biodegradable elastomeric cross-linked polyester material of claim 1 , wherein the polyol component A′ is glycerol and the polyacid component B′ is sebacic acid.

3. The implantable biodegradable elastomeric cross-linked polyester material of claim 1 , wherein the elastomeric cross-linked polyester material has one or more properties selected from the group consisting of:

a Young's modulus of between about 0.5 MPa and about 30 MPa;

a tensile strength of between about 0.5 MPa and about 15 MPa;

an elongation of between about 50% and about 600%;

a size deformation of below about 20% of its initial length, after tensile loading;

a tensile strength stable within about 5% to about 30% of the initial strength over 100 cycles of extension;

a size deformation stable within about 5% to about 30% of the initial length over 100 cycles of extension; and

combinations thereof.

4. The implantable biodegradable elastomeric cross-linked polyester material of claim 1 , wherein the elastomeric cross-linked polyester material has a molecular weight between about 3,000 and about 25,000 Daltons.

5. The implantable biodegradable elastomeric cross-linked polyester material of claim 1 , further comprising a catalyst.

6. The implantable biodegradable elastomeric cross-linked polyester material of claim 1 , wherein the implantable biodegradable elastomeric cross-linked polyester material is free of solvent.

7. The implantable biodegradable elastomeric cross-linked polyester material of claim 1 , further comprising a porogen.

8. The implantable biodegradable elastomeric cross-linked polyester material of claim 1 , wherein the one or more agents are controllably released when the elastomeric cross-linked polyester material biodegrades.

9. A method of making the implantable biodegradable elastomeric cross-linked polyester material of claim 1 comprising the steps of:

(1) mixing a polyester material, a catalyst, and one or more agents selected from the group consisting of therapeutic agents, diagnostic agents, prophylactic agents, nutraceutical agents, and combinations thereof,

wherein the polyester material comprises a plurality of A and B components, wherein the A and B components form a plurality of polymeric backbones formed of (-A-B-) repeat units having the general formula (-A-B-) p , wherein:

p is an integer greater than 1;

the (-A-B-) repeat units have a chemical structure formed when a polyol component A′ is condensed with a polyacid component B′;

at least two of the (-A-B-) repeat units within each of the polymeric backbones have at least one free hydroxyl group present thereon on the A component of the at least two (-A-B-) repeat units within the polymeric backbones;

wherein the polyester material has a molecular weight between about 3,000 and about 50,000 Daltons;

wherein the at least one free hydroxyl group and the polyisocyanate crosslinker are at a molar ratio of between about 1:0.2 and about 1:0.8 or between about 1:1.2 and about 1:1.5; and

(2) combining the polyester material with a polyisocyanate crosslinker to form a reaction mixture and optionally injecting the reaction mixture formed therefrom into a mold or an individual;

wherein the implantable biodegradable elastomeric cross-linked polyester material is produced from the reaction mixture as a plurality of urethane crosslinks form and covalently crosslink the polymeric backbones between the A components of the at least two (-A-B-) repeat units within each of the polymeric backbones.

10. The method of claim 9 , wherein the step of mixing is conducted in the presence of at least one solvent.

11. The method of claim 9 , wherein the step of combining is conducted in the absence of solvent.

12. The method of claim 9 , wherein the polyol component A′ is glycerol and the polyacid component B′ is sebacic acid.

13. The method of claim 9 , wherein the step of combining is conducted at a temperature less than 60° C.

14. The method of claim 9 , wherein the step of combining is conducted at a temperature less than 50° C.

15. The method of claim 9 , wherein the step of combining is conducted at a temperature less than 45° C.

16. The method of claim 9 , wherein the step of combining is conducted at room temperature.

17. The method of claim 9 , wherein the reaction mixture is injected into the individual.

18. The method of claim 9 , wherein all steps of the method are performed within 12 hours, 24 hours, or 48 hours.

19. The method of claim 9 , further comprising a step of exposing the reaction mixture of step (2) to a vacuum.