BIODEGRADABLE POLYESTER BLENDS FOR BIOMEDICAL APPLICATION

A new family of bioabsorbable materials suitable for biomedical applic ations was designed and prepared by means of blending of some availabl e polyesters to develop new biodegradable materials tailored for diffe rent requirements. Multiphase polymer blends containing poly(d, l-lact ide) (PLA), poly(epsilon-caprolactone) (PCL), poly(d, l-lactide-co-pol y(ethylene glycol) (PELA), poly(epsilon-caprolactone)-co-poly(ethylene glycol) (PECL), and poly(beta-hydroxybutyrate) (PHB), PLA/PCL, PELA/P ECL, PHB/PLA, PHB/PELA, PHB/PCL, and PHB/PECL blends were respectively investigated. It was found that PLA/PCL, PHB, and PHB/PLA and PHB/PCL blends were seemingly immiscible, with their morphology and hydrolyti c behavior were determined by the composition of the blends. On the ot her hand, the miscibility of PELA/PECL, PHB/PELA, and PHB/PECL blends was improved by using PELA and/or PECL block copolymers that contained poly(ethylene glycol) (PEG) as compatibilizer. The blends showed to a certain extent miscibility, fine phase morphology, and fast hydrolysi s. (C) 1995 John Wiley and Sons, Inc.