Patent ID: 8481673
Filing Date: 2013-07-09
Classification: A61L,C08G

Abstract:
1. A method for producing a biodegradable and bioabsorbable polymer having a metal catalyst content of less than 1 ppm in terms of a metal and having a weight average molecular weight of 100,000 to 800,000, the method being selected from the group consisting of the following Methods (A) and (B): Method (A) comprising the steps of, (A1) polymerizing lactide and ε-caprolactone at a molar ratio ranging from 40/60 to 60/40 in the presence of a metal catalyst to produce a copolymer, and (A2) washing the copolymer with a mixed solvent comprising acetic acid and isopropanol at a volume ratio ranging from 25/75 to 45/55 at less than 40° C., and drying the copolymer; or Method (B) comprising the steps of, (B1) copolymerizing lactide and ε-caprolactone at a molar ratio ranging from 65/35 to 85/15 in the presence of the metal catalyst to produce a copolymer, and (B2) washing the copolymer with a mixed solvent comprising acetic acid and isopropanol at a volume ratio ranging from 45/55 to 55/45 at less than 40° C., and drying the copolymer.