Synthetic copolymer surgical articles and method of manufacturing the same

• US 4,429,080 A
• Filed: 07/01/1982
• Issued: 01/31/1984
• Est. Priority Date: 07/01/1982
• Status: Expired due to Term

• Current Assignee: Sherwood Services AG
• Original Assignee: American Cyanamid Co (Pfizer Inc.)
• Inventors: Casey, Donald J., Roby, Mark S.
• Primary Examiner(s): Phynes, Lucille M.
• Application Number:
  US06/394,347
• Time in Patent Office: 579 Days
• Field of Search: 525/415, 528/354, 128/333.5, 128/346
• US Class Current: 525/415
• CPC Class Codes: A61K 9/204 Polyesters, e.g. poly(lactide-co-glycolide)
• 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 63/64 Polyesters containing both carboxylic ester groups and carbonate groups

Abstract

A triblock copolymer having a proportion of units having the formula: ##STR1## as the end blocks, and the formula (I) randomly combined with a proportion of units having the formula: ##STR2## as the middle block finds particular advantageous use in manufacturing absorbable monofilament sutures and other surgical articles. A surgical article is manufactured from a synthetic absorbable copolymer formed by copolymerizing glycolide with 1,3-dioxan-2-one (trimethylene carbonate) wherein a combination of the monomers is substantially completely polymerized before the addition of the other monomer in the presence of a difunctional initiator at or below about 180° C.; glycolide is added and the temperature increased up to about the melting point of poly glycolide to form a triblock copolymer with a proportion of units having the formula: ##STR3## as the end blocks, and the formula (I) randomly combined with a proportion of units having the formula: ##STR4## as the middle block.

Claims

1. A surgical article manufactured from a fiber having a bending modulus of less than 500,000 psi, said fiber manufactured from a triblock copolymer comprising a proportion of units having the formula:

##STR13## as the end blocks, said formula (I) as an end block having a hydrogen atom attached to the terminal oxygen atom, and the formula (I) randomly combined with a proportion of units having the formula;

##STR14## as the middle block wherein the middle block comprises 70-95 percent, by weight, of units of formula II and the total copolymer comprises 30-40 percent, by weight, of units of formula II.

2. A method for the manufacture of a surgical article manufactured from a synthetic absorbable copolymer formed by copolymerizing glycolide with 1,3-dioxan-2-one wherein a combination of the monomers is substantially completely polymerized before the addition of the other monomer, the improvement comprising substantially completely polymerizing the combination in the presence of a difunctional initiator at about 180°

C.;

increasing the temperature up to about the melting point of polyglycolide; and

adding glycolide to form a triblock copolymer comprising a proportion of units having the formula;

##STR15## as the end blocks, and the formula (I) randomly combined with a proportion of units having the formula;

##STR16## as the middle block.

3. A method of claim 2 wherein the initiator is selected from the group consisting of a glycol or a polyol.

4. A method of claim 3 wherein the initiator is a glycol.

5. A method of claim 4 wherein said glycol is diethylene glycol.

6. A method of claim 2 or 4 wherein the polymerizing of said combination is at a temperature of about 160°

C. to 190°

C.

7. A method of claim 6 wherein said temperature is about 180°

C.

8. A method of claim 2 or 7 wherein said middle block is about 20-60 percent by weight.

9. A method of claim 8 wherein the middle block comprises 70-95 percent, by weight, of units of formula II and the total copolymer comprises 30-40 percent, by weight, of units of formula II.

10. A surgical article manufactured from copolymer made according to a method of claim 2 or 9.