Biodegradable copolyester, molded article produced therefrom and process for producing the molded article

A molded article produced by melt-forming a biodegradable copolyester comprising an L-lactic acid and/or D-lactic acid component as a component and having a weight average molecular weight of at least 50,000, said copolyester being produced by copolymerizing said lactic acid component with at least one member of (A) a polyethylene glycol having a number average molecular weight of at least 300, (B) an aliphatic polyester and (C) a sulfo group-containing aromatic compound having two ester-forming groups.

A process for producing a molded article of a biodegradable copolyester, which comprises subjecting a molten mixture containing at least one lactic acid component selected from the group consisting of L-lactic acid, D-lactic acid, L-lactide and D-lactide and at least one member selected from the group consisting of (A) a polyethylene glycol having a number average molecular weight of at least 300, (B) an aliphatic polyester and (C) a sulfo group-containing aromatic compound having two ester-forming groups to a melt-polymerization in a continuous polymerization manner for less than one hour to produce a biodegradable copolyester having a weight average molecular weight of at least 50,000, introducing said copolyester directly to a molding machine without solidification and pelletization thereof, and melt-forming said copolyester into an article.