title: PLLA-grafted cellulose nanocrystals: Role of the CNC content and grafting on the PLA bionanocomposite film properties.
abstract: Cellulose nanocrystals (CNC), extracted from microcrystalline cellulose by acid hydrolysis, were grafted by ring opening polymerization of L-Lactide initiated from the hydroxyl groups available at their surface and two different CNC:L-lactide ratios (20:80 and 5:95) were obtained. The resulting CNC-g-PLLA nanohybrids were incorporated in poly(lactic acid) (PLA) matrix by an optimized extrusion process at two different content (1 wt.% and 3 wt.%) and obtained bionanocomposite films were characterized by thermal, mechanical, optical and morphological properties. Thermal analysis showed CNC grafted with the higher ratio of lactide play a significant role as a nucleating agent. Moreover, they contribute to a significant increase in the crystallization rate of PLA, and the best efficiency was revealed with 3 wt.% of CNC-g-PLLA. This effect was confirmed by the increased in Young's modulus, suggesting the CNC graft ratio and content contribute significantly to the good dispersion in the matrix, positively affecting the final bionanocomposite properties.
authors.affiliation: Macromolecular Chemistry Research Group (LABQUIMAC), Department of Physical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa 48940, Spain.
authors.forename: Erlantz
authors.initials: E
authors.lastname: Lizundia
authors.affiliation: University of Perugia, Civil and Environmental Engineering Department, UdR INSTM, Strada di Pentima 4, 05100 Terni, Italy. Electronic address: elena.fortunati@unipg.it.
authors.forename: Elena
authors.initials: E
authors.lastname: Fortunati
authors.affiliation: University of Perugia, Civil and Environmental Engineering Department, UdR INSTM, Strada di Pentima 4, 05100 Terni, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Dominici
authors.affiliation: Macromolecular Chemistry Research Group (LABQUIMAC), Department of Physical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa 48940, Spain; Basque Center for Materials, Applications and Nanostructures (BCMaterials), Parque Tecnológico de Bizkaia, Ed. 500, Derio 48160, Spain.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Vilas
authors.affiliation: Macromolecular Chemistry Research Group (LABQUIMAC), Department of Physical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa 48940, Spain; Basque Center for Materials, Applications and Nanostructures (BCMaterials), Parque Tecnológico de Bizkaia, Ed. 500, Derio 48160, Spain.
authors.forename: Luis Manuel
authors.initials: LM
authors.lastname: León
authors.affiliation: University of Perugia, Civil and Environmental Engineering Department, UdR INSTM, Strada di Pentima 4, 05100 Terni, Italy. Electronic address: ilaria.armentano@unipg.it.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Armentano
authors.affiliation: University of Perugia, Civil and Environmental Engineering Department, UdR INSTM, Strada di Pentima 4, 05100 Terni, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Torre
authors.affiliation: University of Perugia, Civil and Environmental Engineering Department, UdR INSTM, Strada di Pentima 4, 05100 Terni, Italy.
authors.forename: Josè M
authors.initials: JM
authors.lastname: Kenny
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D003460:Crystallization; D055119:Elastic Modulus; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D011091:Polyesters / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D011091:Polyesters; C033616:poly(lactide); D002482:Cellulose; C109691:microcrystalline cellulose
keywords: Cellulose nanocrystals; Grafting; Interfacial compatibility; Poly(lactic acid); Renewable bionanocomposites