title: Starch and cellulose nanocrystals together into thermoplastic starch bionanocomposites.
abstract: In the present work, thermoplastic maize starch based bionanocomposites were prepared as transparent films, plasticized with 35% of glycerol and reinforced with both waxy starch (WSNC) and cellulose nanocrystals (CNC), previously extracted by acidic hydrolysis. The influence of the nanofiller content was evaluated at 1 wt.%, 2.5 wt.% and 5 wt.% of WSNC. The effect of adding the two different nanoparticles at 1 wt.% was also investigated. As determined by tensile measurements, mechanical properties were improved at any composition of WSNC. Water vapour permeance values maintained constant, whereas barrier properties to oxygen reduced in a 70%, indicating the effectiveness of hydrogen bonding at the interphase. The use of CNC or CNC and WSNC upgraded mechanical results, but no significant differences in barrier properties were obtained. A homogeneous distribution of the nanofillers was demonstrated by atomic force microscopy, and a shift of the two relaxation peaks to higher temperatures was detected by dynamic mechanical analysis.
authors.affiliation: Materials+Technologies' Group, Department of Chemical and Environmental Engineering, Polytechnic School, University of the Basque Country, Pza. Europa 1, 20018 Donostia-San Sebastián, Spain.
authors.forename: Kizkitza
authors.initials: K
authors.lastname: González
authors.affiliation: Materials+Technologies' Group, Department of Chemical and Environmental Engineering, Polytechnic School, University of the Basque Country, Pza. Europa 1, 20018 Donostia-San Sebastián, Spain.
authors.forename: Aloña
authors.initials: A
authors.lastname: Retegi
authors.affiliation: POLYMAT, Department of Polymer Science and Technology, Faculty of Chemistry, University of the Basque Country, PO Box 1072, 20080 Donostia-San Sebastián, Spain.
authors.forename: Alba
authors.initials: A
authors.lastname: González
authors.affiliation: Materials+Technologies' Group, Department of Chemical and Environmental Engineering, Polytechnic School, University of the Basque Country, Pza. Europa 1, 20018 Donostia-San Sebastián, Spain.
authors.forename: Arantxa
authors.initials: A
authors.lastname: Eceiza
authors.affiliation: Materials+Technologies' Group, Department of Chemical and Environmental Engineering, Polytechnic School, University of the Basque Country, Pza. Europa 1, 20018 Donostia-San Sebastián, Spain. Electronic address: nagore.gabilondo@ehu.es.
authors.forename: Nagore
authors.initials: N
authors.lastname: Gabilondo
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D004355:Drug Stability; D006868:Hydrolysis; D055595:Mechanical Phenomena; D053761:Nanocomposites / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D010969:Plastics / Q000737:chemistry*; D013213:Starch / Q000737:chemistry*; D013696:Temperature
chemical_list: D010969:Plastics; D002482:Cellulose; D013213:Starch
keywords: Bionanocomposite; Morphology; Polysaccharide nanocrystals; Thermal, mechanical and barrier properties; Thermoplastic starch