Bioabsorbable fibers and reinforced composites produced therefrom

• US 6,511,748 B1
• Filed: 06/30/2000
• Issued: 01/28/2003
• Est. Priority Date: 01/06/1998
• Status: Expired due to Fees

• Current Assignee: Aderans Research Institute Incorporated
• Original Assignee: Aderans Research Institute Incorporated
• Inventors: Barrows, Thomas H.
• Primary Examiner(s): DIXON, MERRICK L
• Application Number:
  US09/582,833
• Time in Patent Office: 942 Days
• Field of Search: 428/364, 428/292.1, 428/373, 428/374, 428/375, 428/361
• US Class Current: 428/373
• CPC Class Codes: A61B 17/72 Intramedullary pins, nails or other devices A61B17/744 takes precedence
• CPC Class Codes: A61B 2017/00004 (bio)absorbable, (bio)resorbable, resorptive for implantable prostheses A61F2210/0004
• CPC Class Codes: A61F 2/30965 Reinforcing the prosthesis by embedding particles or fibres during moulding or dipping
• CPC Class Codes: A61F 2/4455 for the fusion of spinal bodies, e.g. intervertebral fusion of adjacent spinal bodies, e.g. fusion cages intervertebral discs A61F2/442
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61L 27/48 with macromolecular fillers
• CPC Class Codes: A61L 31/06 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds A61L31/041 takes precedence
• CPC Class Codes: A61L 31/12 Composite materials, i.e. containing one material dispersed in a matrix of the same or different material
• CPC Class Codes: A61L 31/128 containing other specific inorganic fillers not covered by A61L31/126 or A61L31/127
• CPC Class Codes: A61L 31/148 Materials at least partially resorbable by the body
• CPC Class Codes: C08L 67/04 Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence
• CPC Class Codes: D01F 6/00 Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
• CPC Class Codes: D01F 8/14 with at least one polyester as constituent
• CPC Class Codes: Y10T 428/249924 Noninterengaged fiber-containing paper-free web or sheet which is not of specified porosity
• CPC Class Codes: Y10T 428/24994 Fiber embedded in or on the surface of a polymeric matrix
• CPC Class Codes: Y10T 428/2907 with coating or impregnation
• CPC Class Codes: Y10T 428/2929 Bicomponent, conjugate, composite or collateral fibers or filaments [i.e., coextruded sheath-core or side-by-side type]
• CPC Class Codes: Y10T 428/2931 Fibers or filaments nonconcentric [e.g., side-by-side or eccentric, etc.]
• CPC Class Codes: Y10T 428/2933 : Coated or with bond, impregnation or core

Abstract

This invention relates to bioabsorbable fibers, comprising a semicrystalline fiber-forming core polymer and an amorphous sheath polymer, wherein the core polymer and sheath polymer are separately melt extruded and connected to one another through an adhesive bond. The present invention also relates to reinforced composites of the bioabsorbable fibers, and to devices comprising the reinforced composites. The devices are suitable for in vivo implantation. Some embodiments of the present devices can also support high loads, making then useful for fracture fixation and spinal fusion. The invention also relates to methods of making the various materials of the invention.

Claims

1. A bioabsorbable fiber comprising a core of a semicrystalline fiber-forming bioabsorbable core polymer with a crystalline core melting temperature, and a sheath of an amorphous bioabsorbable sheath polymer with a softening point below the crystalline core melting temperature, wherein the core polymer and sheath polymer are separately melt extruded, and die sheath is connected to the core through an adhesive bond.

2. The bioabsorbable fiber of claim 1, wherein the core polymer is selected from the group consisting of poly(L-lactide), polyglycolide, poly(epsilon-caprolactone), polydioxanone, poly(ester-amide)s, any combination thereof, and any copolymers thereof wherein trimethylene carbonate is a comonomer.

3. The bioabsorbable fiber of claim 1, wherein the sheath polymer comprises at least one polymer selected from the group consisting of poly(ester-amide)s, tyrosine-derived polycarbonates, poly(trimethylene carbonate), poly(dl-lactide), polydioxanone, and any copolymer, mixture, or blend thereof.

4. The bioabsorbable fiber of claim 1, wherein the sheath polymer comprises a copolymer which is the product of copolymerization of at least two monomers selected from the group of monomers consisting of epsilon-caprolactone, trimethylene carbonate, L-lactide, dl-lactide, glycolide, and para-dioxanone.

5. The bioabsorbable fiber of claim 1, wherein the core polymer is poly(L-lactide) and the sheath polymer is a block copolymer of poly(ester-amide) and L-lactide.

6. The bioabsorbable fiber of claim 5, wherein the sheath polymer is a block copolymer of L-lactide and 1,6-hexanediol terminated poly[2,5-dioxahexane-1,6-di(carbonyloxy)hexane-1,6-di(amidocarbonylpentamethylene)].

7. The bioabsorbable fiber of claim 1, wherein the sheath is bound to the core with sufficient strength that the sheath elongates with the core and does not separate therefrom through hot stretching, elongation, and cooling of the fiber.