Absorbable composition

• US 5,314,989 A
• Filed: 05/03/1993
• Issued: 05/24/1994
• Est. Priority Date: 04/17/1991
• Status: Expired due to Term

• Current Assignee: United States Surgical Corporation (Medtronic Plc)
• Original Assignee: United States Surgical Corporation (Medtronic Plc)
• Inventors: Kennedy, John, Muth, Ross R., Kaplan, Donald S.
• Primary Examiner(s): Nutter, Nathan M.
• Assistant Examiner(s): Dodson, Shelley A.
• Application Number:
  US08/058,515
• Time in Patent Office: 386 Days
• Field of Search: 128/335.5, 523/105, 525/408, 525/415, 528/354, 528/357, 606/230, 606/231
• US Class Current: 528/354
• CPC Class Codes: A61L 17/12 Homopolymers or copolymers of glycolic acid or lactic acid
• CPC Class Codes: C08G 63/08 Lactones or lactides
• CPC Class Codes: C08G 63/664 derived from hydroxy carboxylic acids

Abstract

A block copolymer for use in the fabrication of bioabsorbable articles such as monofilament surgical sutures is prepared by copolymerizing one or more hard phase forming monomers and 1,4-dioxan-2-one, and then polymerizing one or more hard phase forming monomers with the dioxanone-containing copolymer.

Claims

1. A block copolymer which comprises a proportion of units of one or more hard phase forming monomers as one of said blocks, and another of said blocks comprising a proportion of units having the formula:

##STR4## randomly combined with a proportion of units of one or more hard phase forming monomers.

2. The block copolymer of claim 1 wherein said block copolymer is a diblock copolymer.

3. The block copolymer of claim 1 wherein said one or more hard phase forming monomers are selected from the group consisting of glycolide, lactide and mixtures thereof.

4. The block copolymer of claim 1 wherein from about 1 weight % to about 20 weight % of the block copolymer comprises units having the formula:

##STR5##

5. The block copolymer of claim 1 wherein the hard phase forming monomers comprise about 10 weight % to about 40 weight % of the block containing units of formula:

##STR6##

6. A surgical article manufactured from a block copolymer which comprises a proportion of units of one or more hard phase forming monomers as one of said blocks, and another of said blocks comprising a proportion of units having the formula:

##STR7## randomly combined with a proportion of units of one or more hard phase forming monomers.

7. The surgical article of claim 6 wherein said block copolymer is a diblock copolymer.

8. The surgical article of claim 6 wherein said surgical article is a suture.

9. The surgical article of claim 8 wherein said suture is a monofilament suture.

10. The surgical article of claim 6 wherein from about 1 weight % to about 20 weight % of the block copolymer comprises units having the formula:

##STR8##

11. A method for preparing a bioabsorbable block copolymer, comprising:

a) polymerizing a mixture of one or more hard phase forming monomers and 1,4-dioxan-2-one at a first reaction temperature to create a copolymer thereof;

b) polymerizing one or more hard phase forming monomers with the copolymer of step (a) at a second reaction temperature to create the bioabsorbable block copolymer.

12. The method of claim 11 wherein said block copolymer is a diblock copolymer.

13. The method of claim 11 wherein said first reaction temperature comprises a temperature of from about 100°

C. to about 150°

C.

14. The method of claim 11 wherein said second reaction temperature comprises a temperature of from about 200°

C. to about 250°

C.

15. The method of claim 11 wherein step (a) is carried out in the presence of a polymerization catalyst.

16. The method of claim 15 wherein said catalyst is stannous octoate.

17. The method of claim 15 wherein said catalyst is selected from the group consisting of stannous chloride, dibutyl tin dilaurate, dibutyl tin diacetate, dibutyl tin dichloride, stannic chloride pentahydrate, aluminum isopropoxide, antimony trioxide, stannic fluoride, stannous citrate, stannous acetate, antimony trifluoride, tin tetraisopropoxide, lead oxide, tetraisopropyl titanate, titanium acetyl acetonate, tetraoctylene glycol titanate, boron trifluoride etherate, and aluminum trichloride.

18. A method for making a bioabsorbable surgical article, comprising:

a) polymerizing a mixture of one or more hard phase forming monomers and 1,4-dioxan-2-one at a first reaction temperature to create a copolymer thereof;

b) polymerizing one or more hard phase forming monomers with the copolymer of step (a) at a second reaction temperature to create a bioabsorbable block copolymer;

c) forming a surgical article from said block copolymer.

19. The method of claim 18 wherein said forming includes the step of extruding the block copolymer into a filament.

20. The method of claim 19 wherein the bioabsorbable surgical article comprises a suture.

21. The method of claim 20 additionally comprising drawing the suture and relaxing the suture.

22. The method of claim 18 wherein said block copolymer is a diblock copolymer.

23. The method of claim 18 wherein said first reaction temperature comprises a temperature of from about 100°

C. to about 150°

C.

24. The method of claim 18 wherein said second reaction temperature comprises a temperature of from about 200°

C. to about 250°

C.

25. The method of claim 18 wherein step (a) is carried out in the presence of a polymerization catalyst.

26. The method of claim 25 wherein said catalyst is stannous octoate.

27. The method of claim 25 wherein said catalyst is selected from the group consisting of stannous chloride, dibutyl tin dilaurate, dibutyl tin diacetate, dibutyl tin dichloride, stannic chloride pentahydrate, aluminum isopropoxide, antimony trioxide, stannic fluoride, stannous citrate, stannous acetate, antimony trifluoride, tin tetraisopropoxide, lead oxide, tetraisopropyl titanate, titanium acetyl acetonate, tetraoctylene glycol titanate, boron trifluoride etherate, and aluminum trichloride.

28. The method of claim 18 wherein from about 55 weight % to about 85 weight % of the block copolymer comprises units derived from glycolide.

29. The method of claim 18 wherein from about 1 weight % to about 20 weight % of the block copolymer comprises units derived from lactide.

30. The method of claim 18 wherein from about 10 weight % to about 40 weight % of the block copolymer comprises units derived from 1,4-dioxan-2-one.