title: High-barrier coated bacterial cellulose nanowhiskers films with reduced moisture sensitivity.
abstract: This study reports on the development and characterization of bacterial cellulose (BCNW) films coated with hydrophobic layers, presenting enhanced barrier properties. Pure BCNW films showed good transparency and thermal stability, high rigidity and extremely low oxygen permeability at 0%RH. The dramatic increase in oxygen permeability at 80%RH, due to the hydrophilic character of BCNW, was counteracted through coating the films with annealed PLA electrospun nanostructured fibres or hydrophobic silanes. The use of electrospinning was crucial to attain a good adhesion between the hydrophilic BCNW and the hydrophobic PLA layer. After electrospinning, the fibres were homogenised by annealing, thus obtaining a uniform and continuous coating. Coated systems showed a hydrophobic surface and protected the BCNW from moisture, thus reducing ca. 70% the water permeability and up to 97% the oxygen permeability at 80%RH. Furthermore, this novel approach was seen to protect BCNW films from moisture more efficiently than coating with hydrophobic silanes.
authors.affiliation: Novel Materials and Nanotechnology Group, IATA, CSIC, Avda. Agustín Escardino, 7, 46980 Paterna, Valencia, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Martínez-Sanz
authors.forename: Amparo
authors.initials: A
authors.lastname: Lopez-Rubio
authors.forename: Jose M
authors.initials: JM
authors.lastname: Lagaron
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D041822:Gluconacetobacter xylinus / Q000737:chemistry*; D006813:Humidity; D057927:Hydrophobic and Hydrophilic Interactions; D055595:Mechanical Phenomena; D049329:Nanostructures / Q000737:chemistry*; D010969:Plastics / Q000737:chemistry; D011091:Polyesters / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D012821:Silanes / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D010969:Plastics; D011091:Polyesters; D012821:Silanes; D014867:Water; D011092:Polyethylene Glycols; C033616:poly(lactide); D002482:Cellulose
keywords: Bacterial cellulose; Barrier properties; Electrospinning; Nanowhiskers; Polylactide; Silanes