title: Tunable green oxygen barrier through layer-by-layer self-assembly of chitosan and cellulose nanocrystals.
abstract: We address the oxygen-barrier properties of a nanocomposite created by layer-by-layer assembly of two biopolymers, chitosan (CS) and cellulose, in nanocrystals form (CNs), on an amorphous PET substrate. We systematically investigated the oxygen permeability, morphology, and thickness of the nanocomposite grown under two different pH combinations and with different number of deposition cycles, up to 30 bilayers. Noticeably, the thickness of each deposited bilayer can be largely tuned by the pH value of the solution, from ~7 up to ~26 nm in the tested conditions. By our analysis, it is reliably concluded that such CS/CNs nanocomposite holds promises for gas barrier applications in food and drug packaging as a clear coating on plastic films and tridimensional objects, improving performance and sustainability of the final packages.
authors: DeFENS - Department of Food, Environmental and Nutritional Sciences, Packaging Division, Università degli Studi di Milano, Via Celoria, 2, 20133 Milano, Italy.
authors: Fei
authors: F
authors: Li
authors: Paolo
authors: P
authors: Biagioni
authors: Marco
authors: M
authors: Finazzi
authors: Silvia
authors: S
authors: Tavazzi
authors: Luciano
authors: L
authors: Piergiovanni
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D055772:Green Chemistry Technology; D053758:Nanoparticles / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D010539:Permeability
chemical_list: D002482:Cellulose; D048271:Chitosan; D010100:Oxygen