Abstract
Block copolymers were prepared by ring-opening polymerization of e-caprolactone in the presence of monohydroxyl or dihydroxyl poly(ethylene glycol) (PEG), using Zn powder as catalyst. The resulting PCL-PEG diblock and PCL-PEG-PCL triblock copolymers were characterized by various analytical techniques such as NMR, SEC, DSC and X-ray diffraction. Both copolymers were semi-crystalline polymers, the crystalline structure being of the PCL-type. Films were prepared by casting dichloromethane solutions of the polymers on a glass plate. Square samples with dimensions of 10 x 10 mm were allowed to degrade in a pH = 7.0 phosphate buffer solution containing pseudomonas lipase. Data showed that the introduction of PEG blocks did not decrease the degradation rate of poly(e-caprolactone).