title: Cellulose nanocrystals reinforced environmentally-friendly waterborne polyurethane nanocomposites.
abstract: Focusing on eco-friendly materials, cellulose nanocrystals (CNC) have gained attention as nanoreinforcement due to their exceptional properties conferred by the elevated length/diameter aspect ratio and high specific mechanical properties. Furthermore, their water dispersibility makes them suitable nanoreinforcements for their incorporation in waterborne polyurethanes (WBPU). The possibility of tailoring the properties by varying the composition and nature of the reagents, opens the opportunity for a wide range of applications. Therefore, in this work a WBPU was synthesized for the preparation of nanocomposite films with different CNC content and the properties of the films were analyzed. The effective incorporation of CNC resulted in an increase in moduli and stress at yield besides in an increased thermomechanical stability, reaching the percolation threshold at a 3wt% CNC as determined theoretically. Nevertheless, above the percolation threshold, the presence of agglomerates reduced slightly these values. The prepared nanocomposites showed increased hydrophilicity after CNC addition.
authors.affiliation: Group 'Materials+Technologies', Department of Chemical and Environmental Engineering, Polytechnic School, University of the Basque Country, Pza Europa 1, Donostia-San Sebastian 20018, Spain. Electronic address: arantzazu.santamaria@ehu.eus.
authors.forename: Arantzazu
authors.initials: A
authors.lastname: Santamaria-Echart
authors.affiliation: Group 'Materials+Technologies', Department of Chemical and Environmental Engineering, Polytechnic School, University of the Basque Country, Pza Europa 1, Donostia-San Sebastian 20018, Spain. Electronic address: lorena.ugarte@ehu.eus.
authors.forename: Lorena
authors.initials: L
authors.lastname: Ugarte
authors.affiliation: Group 'Materials+Technologies', Department of Chemical and Environmental Engineering, Polytechnic School, University of the Basque Country, Pza Europa 1, Donostia-San Sebastian 20018, Spain. Electronic address: clara.garcia@ehu.eus.
authors.forename: Clara
authors.initials: C
authors.lastname: García-Astrain
authors.affiliation: Group 'Materials+Technologies', Department of Chemical and Environmental Engineering, Polytechnic School, University of the Basque Country, Pza Europa 1, Donostia-San Sebastian 20018, Spain. Electronic address: aitor.arbelaiz@ehu.eus.
authors.forename: Aitor
authors.initials: A
authors.lastname: Arbelaiz
authors.affiliation: Group 'Materials+Technologies', Department of Chemical and Environmental Engineering, Polytechnic School, University of the Basque Country, Pza Europa 1, Donostia-San Sebastian 20018, Spain. Electronic address: marian.corcuera@ehu.eus.
authors.forename: Maria Angeles
authors.initials: MA
authors.lastname: Corcuera
authors.affiliation: Group 'Materials+Technologies', Department of Chemical and Environmental Engineering, Polytechnic School, University of the Basque Country, Pza Europa 1, Donostia-San Sebastian 20018, Spain. Electronic address: arantxa.eceiza@ehu.eus.
authors.forename: Arantxa
authors.initials: A
authors.lastname: Eceiza
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D055772:Green Chemistry Technology; D057927:Hydrophobic and Hydrophilic Interactions; D055595:Mechanical Phenomena; D053761:Nanocomposites / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D011140:Polyurethanes / Q000737:chemistry*; D013696:Temperature; D014867:Water / Q000737:chemistry*
chemical_list: D011140:Polyurethanes; D014867:Water; D002482:Cellulose
keywords: Cellulose nanocrystals; Mechanical properties; Nanocomposites; Thermomechanical stability; Waterborne polyurethane