title: Photochemical behavior of polylactide/ZnO nanocomposite films.
abstract: This study reports the effect of light on PLA/ZnO nanocomposites films produced by melt-extrusion. The attention focused on the discrimination between the photocatalytic degradation of PLA provoked by ZnO and the UV screening effect of the ZnO nanoparticles. The chemical modifications of PLA induced by UV light irradiation were analyzed using infrared spectroscopy and completed through the analysis of the low-molecular-weight photoproducts using IC and SPME and the characterization of chain scissions with SEC. A comprehensive mechanism for the photooxidation of PLA was then proposed. The results indicated that the photocatalytic activity of ZnO nanoparticles induces the oxidation of PLA. Because ZnO limits the penetration of light inside the samples, this effect mainly concerns the first micrometers at the surface of the exposed samples. Cross-sectional analysis using micro-IR and ATR-IR spectroscopies was performed to highlight the degradation profile in the PLA/ZnO nanocomposites.
authors.affiliation: Clermont Université, Université Blaise Pascal, Clermont-Ferrand, France.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Therias
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Larché
authors.forename: Pierre-Olivier
authors.initials: PO
authors.lastname: Bussière
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Gardette
authors.forename: Marius
authors.initials: M
authors.lastname: Murariu
authors.forename: Philippe
authors.initials: P
authors.lastname: Dubois
mesh_terms: D053761:Nanocomposites / Q000737:chemistry*; D010316:Particle Size; D055668:Photochemical Processes; D011091:Polyesters / Q000737:chemistry*; D013499:Surface Properties; D014466:Ultraviolet Rays; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D011091:Polyesters; C033616:poly(lactide); D015034:Zinc Oxide