title: Preparation of Nanocellulose Reinforced Chitosan Films, Cross-Linked by Adipic Acid.
abstract: Adipic acid, an abundant and nontoxic compound, was used to dissolve and cross-link chitosan. After the preparation of chitosan films through casting technique, the in situ amidation reaction was performed at 80-100 °C as verified by Fourier transform infrared (FT-IR). The reaction was accompanied by the release of water which was employed to investigate the reaction kinetics. Accordingly, the reaction rate followed the first-order model and Arrhenius equation, and the activation energy was calculated to be 18 kJ/mol. Furthermore, the mechanical properties of the chitosan films were comprehensively studied. First, optimal curing conditions (84 °C, 93 min) were introduced through a central composite design. In order to evaluate the effects of adipic acid, the mechanical properties of physically cross-linked (uncured), chemically cross-linked (cured), and uncross-linked (prepared by acetic acid) films were compared. The use of adipic acid improved the tensile strength of uncured and chemically cross-linked films more than 60% and 113%, respectively. Finally, the effect of cellulose nanofibrils (CNFs) on the mechanical performance of cured films, in the presence of glycerol as a plasticizer, was investigated. The plasticized chitosan films reinforced by 5 wt % CNFs showed superior properties as a promising material for the development of chitosan-based biomaterials.
authors.affiliation: Department of Chemical Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran. p.falamarzpour@gmail.com.
authors.forename: Pouria
authors.initials: P
authors.lastname: Falamarzpour
authors.affiliation: Department of Chemical Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran. tbehzad@cc.iut.ac.ir.
authors.forename: Tayebeh
authors.initials: T
authors.lastname: Behzad
authors.affiliation: Swedish Centre for Resource Recovery, University of Borås, 50190 Borås, Sweden. akram.zamani@hb.se.
authors.forename: Akram
authors.initials: A
authors.lastname: Zamani
mesh_terms: D000272:Adipates / Q000737:chemistry*; D000577:Amides / Q000737:chemistry; D002482:Cellulose / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000737:chemistry*; D007700:Kinetics; D055595:Mechanical Phenomena; D008567:Membranes, Artificial; D053758:Nanoparticles / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D000272:Adipates; D000577:Amides; D003432:Cross-Linking Reagents; D008567:Membranes, Artificial; C029900:adipic acid; D002482:Cellulose; D048271:Chitosan
keywords: acetic acid; adipic acid; chitosan; cross-linking; mechanical properties; nanocomposite film