Polymerization of Lactides and Lactones. 10. Synthesis, Characterization, and Application of Amino-Terminated Poly(ethylene glycol)-co-poly(ε-caprolactone) Block Copolymer

The synthesis of hydroxy-terminated poly(ethylene glycol)- co -poly(ε-caprolactone) (MPEG−PCL) was investigated by the reaction of poly(ethylene glycol) and ε-caprolactone in the presence of stannous octoate. The polymerization was proved to be carried out in a controllable way. Bromo-terminated MPEG−PCL copolymer has been synthesized by macromolecular reaction as a possible method to prepare primary amino-terminated MPEG−PCL. The conversion of hydroxy-terminated MPEG−PCL to amino-terminated MPEG−PCL was detected quantitatively. The primary amino-terminated MPEG−PCL was an effective macroinitiator for the ring-opening polymerization of β-benzyl l -aspartate- N -carboxy anhydride. The A−B−C triblock copolymer of MPEG−PCL−PBLA thus synthesized may be used as a new potential biomaterial, which contains both a hydrophilic unit and a hydrophobic unit as well as functional groups.