Patent ID: 8367780

Claim:
An aliphatic polyester copolymer comprising (a) an aliphatic polyester segment and (b) a thermoplastic resin segment that is not an aliphatic polyester, wherein said thermoplastic resin segment (b) has two or more hydroxyl groups and has reactive epoxy groups or phenolic hydroxyl groups at both ends of a molecular chain and wherein said aliphatic polyester copolymer has a number-average molecular weight of about 5,000 to about 300,000 and wherein said thermoplastic resin segment (b) has a number-average molecular weight of about 1,100 to about 20,000, and wherein the aliphatic polyester segment (a) comprises a monomer represented by the following Chemical Formula 1 wherein each R 1 and R 2 is the same or different and is independently hydrogen or C1-C4 alkyl.