title: Increased functional properties and thermal stability of flexible cellulose nanocrystal/ZnO films.
abstract: In this work we attempt to improve the functional properties and thermal stability of cellulose nanocrystal (CNC) films by means of eco-friendly materials and processes. Mechanically flexible films of closely packed CNCs with concentrations up to 5 wt.% of zinc oxide (ZnO) nanoparticles have been prepared by a simple, standard and environmentally friendly method using solely water. Results reveal that ultraviolet light is blocked by 98.5% at 1 wt.% ZnO while good transparency is maintained. A sharp hydrophobicity increase is observed with the addition of ZnO which would enhance the durability of films by decreasing the water diffusion through the material. The thermal degradation activation energy (E) presents an increase of 141%, denoting a high thermal stability of films, which would result beneficial for their potential application in the field of flexible electronics. Mechanical results demonstrate a high structural integrity of CNC/ZnO as a result of the occurring strong cellulosic inter- and intramolecular interactions within the closely packed CNC network. In overall, this work highlights the potential for environmentally friendly processing of sustainable nanostructured functional materials based on cellulose.
authors.affiliation: Macromolecular Chemistry Research Group (LABQUIMAC), Department of Physical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Spain. Electronic address: erlantz.liizundia@ehu.es.
authors.forename: E
authors.initials: E
authors.lastname: Lizundia
authors.affiliation: Macromolecular Chemistry Research Group (LABQUIMAC), Department of Physical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Spain. Electronic address: aurruchi002@ikasle.ehu.eus.
authors.forename: A
authors.initials: A
authors.lastname: Urruchi
authors.affiliation: Macromolecular Chemistry Research Group (LABQUIMAC), Department of Physical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Spain; Basque Center for Materials, Applications and Nanostructures (BCMaterials), Parque Tecnológico de Bizkaia, Ed. 500, Derio 48160, Spain. Electronic address: joseluis.vilas@bcmaterials.net.
authors.forename: J L
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), Spain; Basque Center for Materials, Applications and Nanostructures (BCMaterials), Parque Tecnológico de Bizkaia, Ed. 500, Derio 48160, Spain. Electronic address: luismanuel.leon@ehu.es.
authors.forename: L M
authors.initials: LM
authors.lastname: León
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D004355:Drug Stability; D055772:Green Chemistry Technology; D057927:Hydrophobic and Hydrophilic Interactions; D055595:Mechanical Phenomena; D053758:Nanoparticles / Q000737:chemistry*; D013314:Stress, Mechanical; D013696:Temperature; D013718:Tensile Strength; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D002482:Cellulose; D015034:Zinc Oxide
keywords: Acetone (PubChem CID: 180); Cellulose (PubChem CID: 14055602); Cellulose nanocrystals (CNC); Distilled water (PubChem CID: 962); Methanol (PubChem CID: 887); Renewable materials; Sodium hydroxide (PubChem CID: 14798); Sulfuric acid (PubChem CID: 1118); Surface hydrophobicity; Thermal stability; UV–Vis spectroscopy; Zinc oxide; Zinc oxide (PubChem CID: 14806)