BIO-DEGRADABLE/ABSORBABLE POLYMER HAVING REDUCED METAL CATALYST CONTENT, AND PROCESS FOR PRODUCTION THEREOF

摘要

The present invention provides a safe biodegradable and bioabsorbable polymer having an extremely low metal catalyst content, while retaining the properties desired for a medical implant or the like; and a process for producing the same. Provided are methods for producing the polymer having a metal catalyst content of less than 1 ppm in terms of the metal comprising the steps of (1) copolymerizing lactide and .epsilon.-caprolactone at a molar ratio from 40/60 to 60/40 in the presence of the metal catalyst; and (2) washing the copolymer with a mixed solvent comprising acetic acid and isopropanol at a volume ratio from 25/75 to 45/55 at less than 40�C, and drying the copolymer; or comprising the steps of (1) copolymerizing lactide and s-caprolactone at a molar ratio from 65/35 to 85/15 in the presence of the metal catalyst; and (2) washing the copolymer with a mixed solvent comprising acetic acid and isopropanol at a volume ratio from 45/55 to 55/45 at less than 40�C, and drying the copolymer.