title: Nano-MgO reinforced chitosan nanocomposites for high performance packaging applications with improved mechanical, thermal and barrier properties.
abstract: Chitosan nanocomposite thin films were fabricated by incorporating MgO nanoparticles to significantly improve its physical properties for potential packaging applications. A novel in-situ method was developed to synthesise spherical shaped MgO nanoparticles by heat-treating magnesium carbonate/poly(methyl methacrylate) (PMMA) composite precursor. Optimum mechanical properties of chitosan composites were yielded at 5 (w/w%) of MgO concentration, where tensile stress and elastic modulus significantly improved by 86% and 38%, respectively, compared to those of pure chitosan films. These improvements are due to the interaction of hydroxyl and amine groups of chitosan with MgO as confirmed by FTIR spectroscopy. Fracture surface morphology indicated the interplay between MgO dispersion and aggregation on the mechanical properties at different MgO concentrations. Furthermore, the chitosan/MgO nanocomposites displayed remarkable thermal stability, flame retardant properties (satisfied V0 rating according to the UL-94 standards), UV shielding and moisture barrier properties, which could certainly add value to the packaging material.
authors.affiliation: Sri Lanka Institute of Nanotechnology (SLINTEC), Nanotechnology and Science Park, Pitipana, Homagama, Sri Lanka.
authors.forename: R T
authors.initials: RT
authors.lastname: De Silva
authors.affiliation: Sri Lanka Institute of Nanotechnology (SLINTEC), Nanotechnology and Science Park, Pitipana, Homagama, Sri Lanka.
authors.forename: M M M G P G
authors.initials: MMMGPG
authors.lastname: Mantilaka
authors.affiliation: Sri Lanka Institute of Nanotechnology (SLINTEC), Nanotechnology and Science Park, Pitipana, Homagama, Sri Lanka.
authors.forename: S P
authors.initials: SP
authors.lastname: Ratnayake
authors.affiliation: Sri Lanka Institute of Nanotechnology (SLINTEC), Nanotechnology and Science Park, Pitipana, Homagama, Sri Lanka; Electrical Engineering Division, Department of Engineering, University of Cambridge, 9 J. J. Thomson Avenue, Cambridge CB3 0FA, UK.
authors.forename: G A J
authors.initials: GAJ
authors.lastname: Amaratunga
authors.affiliation: Sri Lanka Institute of Nanotechnology (SLINTEC), Nanotechnology and Science Park, Pitipana, Homagama, Sri Lanka; Department of Chemistry, University of Colombo, Colombo 3, Sri Lanka. Electronic address: kmnd@chem.cmb.ac.lk.
authors.forename: K M Nalin
authors.initials: KMN
authors.lastname: de Silva
keywords: Chitosan; Mechanical properties; Nano-magnesium oxide; Thermal stability; Thin films