ABSORBABLE COPOLYMER SUTURE

1375008 Filaments of lactide/glycollide copolymers ETHICON Inc 16 Dec 1971 [18 Dec 1970 16 Nov 1971] 58564/71 Heading B5B [Also in Divisions C3 and D1] A packaged suture comprises a sterile absorbable surgical suture in an internally sterile package, the suture being a braided multifilament thread consisting of filaments made by extruding a copolymer obtained by copolymerizing glycollide and L(-)lactide and containing 10-15 mole per cent of lactide and having an inherent viscosity of at least 1À4, as determined on a 0À1 per cent solution in hexafluoroisopropanol at 25‹ C. The filaments are extruded, stretched, annealed, braided, optionally further stretched and annealed, and sterilized by exposure to a wet atmosphere of a fluorochloralkane and ethylene oxide. The filaments may be dyed by addition of a non- toxic dye to the polymer mixture. The copolymerization reaction between the L(-)lactide and glycollide is carried out in a dry container under a blanket of dry nitrogen and is catalysed using stannous octoate. Several examples of reaction conditions are given in the Specification. The copolymer melt is extruded using a screw feed hopper, a metering pump, and a die with the appropriate number of orifices. Several examples of extrusion conditions are given in the Specification. The suture material is cut to suitable length and sterilely packaged with a surgical needle.