Lipase-catalyzed biodegradation of poly(epsilon-caprolactone) blended with various polylactide-based polymers.
Poly(epsilon-caprolactone) was blended with various polylactide-based polymers and processed to films by the solution casting method. Blends of 25/75, 50/50, 75/25, 90/10, and 95/5 (w/w) poly(epsilon-caprolactone)/poly(l-lactide), a 95/5 (w/w) blend of poly(epsilon-caprolactone) with a poly(d-lactide), a 50/50 (w/w) poly(l-lactide)-poly(d-lactide) mixture, and a poly(l-lactide-co-epsilon-caprolactone) copolymer were considered comparatively. The various phase-separated films were allowed to degrade in the presence of Pseudomonas lipase, biodegradation being monitored by proton nuclear magnetic resonance, size exclusion chromatography, differential scanning calorimetry, X-ray diffraction, and environmental scanning electron microscopy. The formation of separated phases during solvent evaporation and their morphologies are discussed. The introduction of poly(l-lactide) dramatically decreased the degradation rate of poly(epsilon-caprolactone)/poly(l-lactide) blends. The higher the percentage of poly(l-lactide), the slower the degradation, while the presence of cracks and increasing the lipase concentration acted in favor of the enzymatic degradation. Long-term enzymatic degradation of the various 95/5 blends was investigated over 480 h. The poly(epsilon-caprolactone) phase was enzymatically degraded by the lipase regardless of the blend type, the degradation rate depending on the nature of the co-components.
Li
Suming
S
Centre de Recherche sur les Biopolymères Artificiels, Faculté de Pharmacie, 15 avenue Charles Flahault, 34060 Montpellier Cedex 2, France.
Liu
Lijian
L
Garreau
Henri
H
Vert
Michel
M
D001673:Biodegradation, Environmental; D008049:Lipase / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008855:Microscopy, Electron, Scanning; D011091:Polyesters / Q000378:metabolism*
D011091:Polyesters; C016240:polycaprolactone; C033616:poly(lactide); D008049:Lipase