Crosslinkable polyisobutylene-based polymers and medical devices containing the same
The present invention pertains to crosslinkable and crosslinked polyisobutylene-based polymers, to compositions that contain such polymers, and to medical devices that are formed using such polymers. According to one aspect, the present invention pertains to crosslinkable and crosslinked compositions that comprise a copolymer that comprises a polyisobutylene segment and two or more reactive groups. According to another aspect, the present invention pertains to medical devices that contain such compositions. According to another aspect, the present invention pertains to methods of making medical devices using such compositions.
1. A crosslinkable composition comprising (a) a polymer comprising a polyisobutylene segment and two or more unsaturated reactive groups, wherein the polymer is a urethane, urea, or urethane/urea copolymer, and (b) a free radical initiator.
2. The crosslinkable composition of claim 1 , wherein the polymer is a low molecular weight copolymer having a number average molecular weight ranging from 1,000 to 150,000 Daltons.
3. The crosslinkable composition of claim 1 , wherein the polymer comprises terminal groups selected from —CH═CH 2 and —CH≡CH.
4. The crosslinkable composition of claim 1 , wherein the polymer comprises terminal groups are selected from −O—[Si(R) 2 O] m —(CH 2 ) p —CH═CH 2 , where R is C1-C4 alkyl, m ranges from 1 to 100 and p ranges from 1 to 10.
5. The crosslinkable composition of claim 1 , wherein the free radical initiator is a free radical thermal initiator or photoinitiator.
6. The crosslinkable composition of claim 1 , wherein said composition is an adhesive that is cured by exposure to radiation, heat, an organometallic catalyst, a crosslinking agent, or a combination of the foregoing.
7. The crosslinkable composition of claim 1 , wherein the composition further comprises a crosslinking agent with multiple unsaturated groups.
8. The crosslinkable composition of claim 1 , wherein the composition further comprises a therapeutic agent.
9. The crosslinkable composition of claim 1 , wherein said polymer further comprises a non-polyisobutylene polymer segment.
10. The crosslinkable composition of claim 9 , wherein the non-polyisobutylene polymer segment is selected from a polyether segment, a fluorinated polyether segment, a fluoropolymer segment, a polyester segment, a polyacrylate segment, a polymethacrylate segment, a polysiloxane segment, a fluorinated polysiloxane, and a polycarbonate segment.
11. The crosslinkable composition of claim 9 , wherein the non-polyisobutylene polymer segment is selected from a polytetramethylene oxide segment, a polyhexamethylene oxide segment, a polydimethylsiloxane segment, a polyperfluoroalkylene oxide segment and a polyhexamethylene carbonate segment.
12. The crosslinkable composition of claim 1 , wherein the copolymer comprises a residue of an aromatic diisocyanate.
13. The crosslinkable composition of claim 1 , wherein the copolymer comprises a chain extender residue.
14. A method of forming a medical device comprising crosslinking a crosslinkable composition in accordance with claim 1 .
15. The method of claim 14 , wherein said crosslinking step is performed in conjunction with a step in which a coating is applied to a medical device component and crosslinked or in which an adhesive is crosslinked to adhere two or more medical device components to one another.
16. The method of claim 14 , wherein said medical device component or components comprise a copolymer that comprises a polyisobutylene segment.
17. The method of claim 14 , where said crosslinking step is performed in conjunction with an injection molding or extrusion operation.
18. A method of forming a medical device comprising crosslinking a crosslinkable composition in accordance with claim 1 on a surface of a polymeric component that comprises a polyisobutylene segment.
19. The method of claim 18 , wherein said crosslinking step is performed in conjunction with a step in which a coating or adhesive layer is applied said medical device component.
20. The method of claim 18 , wherein said medical device component comprises a urethane, urea or urethane/urea copolymer that comprises a polyisobutylene segment.
21. The crosslinkable composition of claim 1 , wherein said polymer comprises more than two reactive groups.
22. The crosslinkable composition of claim 1 , wherein the free radical initiator is a free radical thermal initiator.
23. The crosslinkable composition of claim 1 , wherein the free radical initiator is a free radical photoinitiator.
24. The crosslinkable composition of claim 1 , wherein the polymer is a low molecular weight copolymer having a number average molecular weight ranging from 1,000 to 50,000 Daltons.
25. The crosslinkable composition of claim 1 , wherein the polymer is a low molecular weight copolymer having a number average molecular weight ranging from 1,000 to 20,000 Daltons.
26. The crosslinkable composition of claim 9 , wherein the non-polyisobutylene polymer segment is a poly(vinyl aromatic) segment.
27. The crosslinkable composition of claim 9 , wherein the non-polyisobutylene polymer segment is a polystyrene segment.
28. The crosslinkable composition of claim 9 , wherein the non-polyisobutylene polymer segment is a polyether segment.
29. The crosslinkable composition of claim 9 , wherein the composition further comprises a crosslinking agent with multiple unsaturated groups.
30. The crosslinkable composition of claim 7 , wherein the crosslinking agent comprises a terminally unsaturated polyether segment.