title: Comparative characterization of aqueous dispersions and cast films of different chitin nanowhiskers/nanofibers.
abstract: Water dispersions of TEMPO-oxidized α-chitin nanowhisker (TOChN), partially deacetylated α-chitin nanowhisker/nanofiber mixture (DEChN), HCl-hydrolyzed chitin nanowhisker (HHChN) and squid-pen β-chitin nanofiber (SQChN) were prepared, and the properties of nano-dispersions and their cast films were characterized between the four chitin nano-samples. Because SQChN has the highest aspect ratio, its 0.1% dispersion had the highest shear stress and viscosity at the same shear rate in the four chitin nano-samples, and showed gel-like behavior in the whole shear rate range from 10(-3) to 10(3) s(-1). AFM images of the self-standing films showed that film surfaces consisted of characteristic chitin nano-elements with different morphologies and degrees of orientation between the four chitin samples, whereas all chitin nanowhisker/nanofiber films had similar thermal degradation points at ~200°C. The DEChN film had the highest tensile strength of ~140 MPa, elongation at break of ~10% and light-transmittance of 87% at 400 nm. In contrast, the SQChN film had the lowest tensile strength, Young's modulus and light-transmittance. All chitin nanowhisker/nanofiber films had similar oxygen permeabilities of ~1 mL μm m(-2) day(-1) kPa(-1), which was clearly lower than that (184 mL μm m(-2) day(-1) kPa(-1)) of a poly(lactic acid) film.
authors: Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan.
authors: Yimin
authors: Y
authors: Fan
authors: Hayaka
authors: H
authors: Fukuzumi
authors: Tsuguyuki
authors: T
authors: Saito
authors: Akira
authors: A
authors: Isogai
mesh_terms: D002686:Chitin / Q000737:chemistry*; D003497:Cyclic N-Oxides / Q000737:chemistry; D019344:Lactic Acid / Q000737:chemistry; D046911:Macromolecular Substances / Q000737:chemistry; D018625:Microscopy, Atomic Force / Q000379:methods; D046529:Microscopy, Electron, Transmission / Q000379:methods; D057139:Nanofibers / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D010100:Oxygen / Q000737:chemistry; D011091:Polyesters; D011108:Polymers / Q000737:chemistry; D011312:Pressure; D013499:Surface Properties; D013696:Temperature; D013718:Tensile Strength; D013818:Thermogravimetry / Q000379:methods; D014466:Ultraviolet Rays; D014867:Water / Q000737:chemistry
chemical_list: D003497:Cyclic N-Oxides; D046911:Macromolecular Substances; D011091:Polyesters; D011108:Polymers; D014867:Water; D002686:Chitin; D019344:Lactic Acid; C033616:poly(lactide); D010100:Oxygen; C003959:TEMPO