Synthesis, Characterization and Crystallization of Poly(Ethylene Glycol)-b-Poly(ε-Caprolactone)

A family of poly(ethylene glycol)-b-poly(ε-caprolactone) (PEG-PCL) were synthesized in high yields by the ring-opening polymerization of monomethoxy-terminated poly(ethylene glycol) (mPEG) with ε-caprolactone in the presence of stannous octoate (Sn(Oct)2). Their crystallization behaviors were studied by DSC, XRD. The results illustrated that crystallization behaviors of the copolymers depended on the copolymer composition and the relative length of each block in copolymers. The melting peak of PCL block appeared gradually in the XRD patterns and DSC curves in copolymers, with increasing of the length of PCL blocks.