Abstract
A multiblock copoly (ester-ether) consisting of poly (L-lactic acid) (PLLA) and poly (oxypropylene-co-oxyethylene) (PN) was prepared and characterized. Preparation was done via the solution polycondensation of a thermal oligocondensate of L-lactic acid, a commercially available telechelic polyether Pluronic-F68TM(PN), and decanedioic acid which is a carboxyl/hydroxyl adjusting agent. When stannous oxide was used as the catalyst, the molecular weight of the resultant PLLA/PN block copolymers became very high (and even showed a high PN content) under optimized reaction conditions. The copolymers were melt-spun by conventional methods and drawn at 60°C at the given draw ratio. The resultant fiber showed greater tensile strength and more flexibility, both which correlated with the increase in PN contents. In addition, tissue reactions against the multiblock copolymers were milder than those against PLLA homopolymer. These results show that these multiblock copolymers have great potential as biodegradable sutures and as other biomaterials e. g., scaffolds for tissue regeneration.
