Polyurethane elastomer article with “shape memory” and medical devices therefrom

• US 6,664,335 B2
• Filed: 11/30/2000
• Issued: 12/16/2003
• Est. Priority Date: 11/30/2000
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Krishnan, Mohan
• Primary Examiner(s): Gorr, Rachel
• Application Number:
  US09/728,617
• Publication Number:
  US 20020065373A1
• Time in Patent Office: 1,111 Days
• Field of Search: 525/123, 525/127, 525/455, 522/135, 623/1.19, 623/23.58
• US Class Current: 525/123
• CPC Class Codes: C08F 283/006 on to polymers provided for in C08G18/00 C08F283/004 takes precedence
• CPC Class Codes: C08G 18/724 Combination of aromatic polyisocyanates with (cyclo)aliphatic polyisocyanates
• CPC Class Codes: C08G 18/83 Chemically modified polymers
• CPC Class Codes: C08G 2280/00 Compositions for creating shape memory

Abstract

A polyurethane article with shape memory, comprising a mixture of thermoplastic polyurethane and reactive monomer cross-linker which is formed into a shaped article, irradiated, expanded and applied to a medical device, specifically a biomedical electrical lead.

Claims

1. An apparatus comprising a shape memory, heat shrinkable polyurethane article comprised of thermoplastic urethane polymer and monomer cross-linker, wherein the article is expanded to receive a medical device and shrunk by the application of heat to conform to the medical device, wherein the medical device is a stent.

2. The apparatus of claim 1, wherein the thermoplastic urethane polymer is comprised of aromatic isocyanate.

3. The apparatus of claim 1, wherein the thermoplastic urethane polymer is comprised of aliphatic isocyanate.

4. The apparatus of claim 1, wherein the thermoplastic urethane polymer is comprised of aliphatic isocyanate and aromatic isocyanate.

5. The apparatus of claim 1, wherein the thermoplastic urethane polymer is selected from a group consisting of polyether urethane, polycarbonate urethane or polysiloxane urethane.

6. The apparatus of claim 1, wherein the thermoplastic urethane polymer is polyether urethane.

7. The apparatus of claim 1, wherein the monomer cross-linker is in an amount of about 0.5% to about 15% by weight of the composition of thermoplastic urethane polymer and monomer cross-linker.

8. A medical device encased in a heat shrinkable, shape memory thermoplastic polyurethane article by a process comprising:

irradiating the article;

expanding the article;

placing the article around a medical device assembly; and

heating the article to conform to the medical device assembly, wherein the medical device is a stent.

9. The medical device of claim 8, wherein the shape memory, heat shrinkable polyurethane composition is comprised of one or more thermoplastic polyurethane polymers and one or more reactive monomer cross-linkers.

10. An apparatus comprising:

a stent, wherein the stent is encased in a shape memory, heat shrinkable polyurethane article comprised of thermoplastic urethane polymer and monomer cross-linker, wherein the article is expanded to receive the stent and shrunk by the application of heat to conform to the stent and prevents tissue ingrowth.

11. The apparatus of claim 10, wherein the thermoplastic urethane polymer is comprised of aromatic isocyanate.

12. The apparatus of claim 10, wherein the thermoplastic urethane polymer is comprised of aliphatic isocyanate.

13. An apparatus comprising:

a vascular graft, wherein the graft is encased in a shape memory, heat shrinkable polyurethane article comprised of thermoplastic urethane polymer and monomer cross-linker,

wherein the article is expanded to receive the graft and shrunk by the application of heat to conform to the graft and prevents tissue ingrowth.

14. The apparatus of claim 13, wherein the thermoplastic urethane polymer is comprised of aromatic isocyanate.

15. The apparatus of claim 13, wherein the thermoplastic urethane polymer is comprised of aliphatic isocyanate.

16. An apparatus comprising a shape memory, heat shrinkable polyurethane article comprised of thermoplastic urethane polymer and monomer cross-linker, wherein the article is expanded to receive a medical device and shrunk by the application of heat to conform to the medical device, wherein the medical device is a vascular graft.

17. The apparatus of claim 16, wherein the thermoplastic urethane polymer is comprised of aromatic isocyanate.

18. The apparatus of claim 16, wherein the thermoplastic urethane polymer is comprised of aliphatic isocyanate.

19. The apparatus of claim 16, wherein the thermoplastic urethane polymer is comprised of aliphatic isocyanate and aromatic isocyanate.

20. The apparatus of claim 16, wherein the thermoplastic urethane polymer is selected from a group consisting of polyether urethane, polycarbonate urethane or polysiloxane urethane.

21. The apparatus of claim 16, wherein the thermoplastic urethane polymer is polyether urethane.

22. The apparatus of claim 16, wherein the monomer cross-linker is in an amount of about 0.5% to about 15% by weight of the composition of thermoplastic urethane polymer and monomer cross-linker.

23. A medical device encased in a heat shrinkable, shape memory thermoplastic polyurethane article by a process comprising:

irradiating the article;

expanding the article;

placing the article around a medical device assembly; and

heating the article to conform to the medical device assembly, wherein the medical device is a vascular graft.

24. The medical device of claim 23, wherein the shape memory, heat shrinkable polyurethane composition is comprised of one or more thermoplastic polyurethane polymers and one or more reactive monomer cross-linkers.