title: Microfibrillated cellulose and borax as mechanical, O₂-barrier, and surface-modulating agents of pullulan biocomposite coatings on BOPP.
abstract: Multifunctional composite coatings on bi-oriented polypropylene (BOPP) films were obtained using borax and microfibrillated cellulose (MFC) added to the main pullulan coating polymer. Spectroscopy analyses suggested that a first type of interaction occurred via hydrogen bonding between the C6OH group of pullulan and the hydroxyl groups of boric acid, while monodiol and didiol complexation represented a second mechanism. The deposition of the coatings yielded an increase in the elastic modulus of the entire plastic substrate (from ∼2GPa of the neat BOPP to ∼3.1GPa of the P/B+/MFC-coated BOPP). The addition of MFC yielded a decrease of both static and kinetic coefficients of friction of approximately 22% and 25%, respectively, as compared to the neat BOPP. All composite coatings dramatically increased the oxygen barrier performance of BOPP, especially under dry conditions. The deposition of the high hydrophilic coatings allowed to obtain highly wettable surfaces (water contact angle of ∼18°).
authors.affiliation: DeFENS, Department of Food, Environmental and Nutritional Sciences-Packaging Division, University of Milan, Milan, Italy.
authors.forename: Carlo A
authors.initials: CA
authors.lastname: Cozzolino
authors.affiliation: DeFENS, Department of Food, Environmental and Nutritional Sciences-Packaging Division, University of Milan, Milan, Italy.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Campanella
authors.affiliation: Fatsa Faculty of Marine Science, Department of Marine Science and Technology Engineering, Ordu University, Ordu, Turkey.
authors.forename: Hasan
authors.initials: H
authors.lastname: Türe
authors.affiliation: Department of Fibre and Polymer Technology, School of Chemical Science and Engineering, KTH Royal Institute of Technology, Stockholm, Sweden.
authors.forename: Richard T
authors.initials: RT
authors.lastname: Olsson
authors.affiliation: DeFENS, Department of Food, Environmental and Nutritional Sciences-Packaging Division, University of Milan, Milan, Italy. Electronic address: stefano.farris@unimi.it.
authors.forename: Stefano
authors.initials: S
authors.lastname: Farris
mesh_terms: D001881:Borates / Q000737:chemistry*; D002482:Cellulose / Q000737:chemistry*; D055119:Elastic Modulus; D005936:Glucans / Q000737:chemistry*; D008420:Manufactured Materials; D010100:Oxygen / Q000737:chemistry; D028222:Picea; D028223:Pinus; D011126:Polypropylenes / Q000737:chemistry*; D013499:Surface Properties; D013718:Tensile Strength; D014867:Water / Q000737:chemistry; D017155:Wettability
chemical_list: D001881:Borates; D005936:Glucans; D011126:Polypropylenes; D014867:Water; C018851:borax; C009109:pullulan; D002482:Cellulose; D010100:Oxygen
keywords: Borax (PubChem CID: 10219853); Composite coatings; Contact angle; Food packaging; Oxygen permeability; Pullulan (PubChem CID: 92024139)