Toughened Polylactic Acid Polymers and Copolymers

Abstract

Toughened compositions of PLA and PLA copolymers are disclosed, which also have low tensile modulus values and greater elongation to break. These toughened compositions are prepared by blending PLA and PLA copolymers with poly-4-hydroxybutyrate, and copolymers thereof. Blending of poly-4-hydroxybutyrate with PLA and its copolymers has been found to impart advantageous properties to the resulting blend. These compositions, and objects formed from these compositions, have improved toughness and lower stiffness than polylactic acid polymers or copolymers alone.

Description

Claims

1. A polymer composition comprising polylactic acid polymer or copolymer and a polymer or copolymer comprising 4-hydroxybutyrate, wherein the elongation to break of the composition is greater than 3%.

2. The composition of claim 1 wherein the modulus of the composition is less than 700 kgf/mm2.

3. The composition of claim 1 comprising a poly-4-hydroxybutyrate homopolymer.

4. The composition of claim 1 comprising poly-3-hydroxybutyrate-co-4-hydroxybutyrate.

5. The composition of claim 1 comprising a polyhydroxy acid selected from the group consisting of poly-L-lactic acid, poly-D-lactic acid, and poly-D,L-lactic acid.

6. The composition of claim 5 wherein the composition comprises polylactic-co-glycolic acid.

7. The composition of claim 1 further comprising one or more additives selected from the group consisting of plasticizers, nucleants, compatibilizers, therapeutic, prophylactic or diagnostic agents, radiolabelled substances, imaging agents, radiopaque markers, contrast agents, anti-oxidants, dyes, viscosity modifiers, and odor control agents.

8. A method of producing a shaped object comprising melting a polymer composition comprising polylactic acid polymer or copolymer and a polymer or copolymer comprising 4-hydroxybutyrate, wherein the elongation to break of the composition is greater than 3%, and producing a shaped object therefrom by extrusion, molding, coating, spinning, blowing, thermoforming or calendaring processes, or combinations of these processes.

9. The method of claim 8 wherein the shaped object is a medical device selected from the group consisting of sutures, suture fasteners, meniscus repair devices, rivets, tacks, staples, screws, bone plates and bone plating systems, biocompatible coatings, rotator cuff repair devices, surgical mesh, medical textiles or drapes, repair patches, slings, cardiovascular patches, tissue engineering scaffolds, vascular grafts, vascular closure devices, catheter balloons, anti-adhesion devices, drug delivery devices, embolization particles, orthopedic pins, adhesion barriers, stents, embolization coils, guided tissue repair/regeneration devices, articular cartilage repair devices, nerve guides, tendon repair devices, intracardiac septal defect repair devices, pericardial patches, bulking and filling agents, vein valves, bone marrow scaffolds, meniscus regeneration devices, ligament and tendon grafts, ocular cell implants, spinal fusion cages, imaging devices, skin substitutes, dural substitutes, bone graft substitutes, bone dowels, wound dressings, and hemostats.

10. The method of claim 8 wherein the shaped object can be used as or in packaging, personal hygiene products, bags, utensils, disposable or compostable articles, garments, surgical drapes, and gloves.

11. A medical device comprising a polymer composition comprising polylactic acid polymer and copolymer and a polymer or copolymer comprising 4-hydroxybutyrate, wherein the elongation to break of the composition is greater than 3%.

12. The medical device of claim 11 wherein the device is a suture, suture fastener, meniscus repair device, rivet, tack, staple, screw, bone plate, bone plating system, biocompatible coating, rotator cuff repair device, surgical mesh, medical textile, repair patch, sling, cardiovascular patche, tissue engineering scaffold, vascular graft, vascular closure device, catheter balloon, anti-adhesion device, drug delivery device, embolization particle, orthopedic pin, adhesion barrier, stent (including coronary stents, peripheral stents, carotid stents, biliary stents, gastroenterology stents, urology stents, and neurology stents), embolization coil, guided tissue repair/regeneration device, articular cartilage repair device, nerve guide, tendon repair device, intracardiac septal defect repair device (including, but not limited to, atrial septal defect repair devices and PFO closure devices, and left atrail appendage (LAA) closure devices), pericardial patch, bulking and filling agent, vein valves, bone marrow scaffold, meniscus regeneration device, ligament graft, tendon graft, ocular cell implant, spinal fusion cage, imaging device, skin substitute, dural substitute, bone graft substitute, bone dowel, would dressing, or a hemostat.

13. A shaped object comprising a polymer composition comprising polylactic acid polymer or copolymer and a polymer or copolymer comprising 4-hydroxybutyrate, wherein the elongation to break of the composition is greater than 3%.

14. The shaped object of claim 13 where the object is a disposable article, compostable article, packaging, personal hygiene product, textile, fiber, film, molded object, bag, utensil, garment, surgical drape, or glove.