Journal of Applied Polymer Science, Vol.84, No.9, 1729-1736, 2002
Synthesis and characterization of poly(L-lactide)-poly(ethylene glycol) multiblock copolymers
Poly(L-lactide)-poly(ethylene glycol) multiblock copolymers with predetermined block lengths were synthesized by polycondensation of PLA diols and PEG diacids. The reaction was carried out under mild conditions, using dicyclohexylcarbodiimide as the coupling agent and dimethylaminopyridine as the catalyst. The resulting copolymers were characterized by various analytical techniques, such as GPC, viscometry, H-1-NMR, FTIR, DSC, X-ray diffractometry, and contact angle measurement. The results indicated that these copolymers presented outstanding properties pertinent to biomedical use, including better miscibility between the two components, low crystallinity, and hydrophilicity. Moreover, the properties of the copolymers can be modulated by adjusting the block length of the two components or the reaction conditions.