Abstract
Triblock copolymers of e-caprolactone and L-lactide with different molar ratios were prepared via sequential ring opening polymerization (ROP) of both monomers. The resulting PCL-PLLA-PCL block copolymers were characterized by using NMR, SEC, DSC and XRD. The triblock copolymers exhibited only one melting peak corresponding to the PCL block. Enzyme-catalyzed biodegradation of solution cast films was investigated at 37 oC in the presence of proteinase K or pseudomonas lipase. It was observed that in the PCL-PLLA-PCL block copolymers, the PLLA component retarded the degradation of the block copolymer. The degradation of PCL-PLLA-PCL films by pseudomonas lipase seems to proceed according to surface erosion mechanism. From 1HNMR studies, there were no significant changes in their chemical compositions.