Biodegradable ABA triblock copolymers with poly(ethylene oxide) and poly(glycolic acid-valine) blocks were synthesized via ring-opening polymerization of cyclo(glycolic acid-valine) using Ca-alcoholates of hydroxy-telechelic PEO as the initiator. The L-valine residue racemized during copolymerization of cyclo(glycolic acid-valine). The crystallization of the block copolymers decreases with decreasing PEO content in the triblock copolymers and with increasing length of the poly(glycolic acid-valine) block.