Pore Size Determination of TEMPO-Oxidized Cellulose Nanofibril Films by Positron Annihilation Lifetime Spectroscopy
| Autor: | Ryoichi Suzuki, Hayaka Fukuzumi, Tsuguyuki Saito, Yoshiaki Kumamoto, Toshiyuki Ohdaira, Shinichiro Iwamoto, Akira Isogai |
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| Rok vydání: | 2011 |
| Předmět: |
Materials science
Polymers and Plastics Surface Properties Oxidized cellulose Nanofibers Bioengineering engineering.material Microscopy Atomic Force Permeability Cyclic N-Oxides Biomaterials Oxygen permeability chemistry.chemical_compound Materials Chemistry Relative humidity Carboxylate Cellulose Porosity Spectroscopy Spectrum Analysis Pulp (paper) Oxidants Oxygen chemistry Chemical engineering engineering Oxidation-Reduction |
| Zdroj: | Biomacromolecules. 12:4057-4062 |
| ISSN: | 1526-4602 1525-7797 |
| DOI: | 10.1021/bm201079n |
| Popis: | Wood cellulose nanofibril films with sodium carboxylate groups prepared from a 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized pulp exhibited an extremely low oxygen permeability of 0.0008 mL μm m(-2) day(-1) kPa(-1) at 0% relative humidity (RH). Positron annihilation lifetime spectroscopy (PALS) was used to determine the pore sizes in wood and tunicate TEMPO-oxidized cellulose nanofibril (TOCN-COONa) films in a vacuum (i.e., at 0% RH). PALS analysis revealed that the pore size of the wood TOCN-COONa films remained nearly at 0.47 nm from the film surface to the interior of the film. This is probably the cause of this high oxygen-barrier properties at 0% RH. The crystalline structure of TOCN-COONa also contributes to the high oxygen-barrier properties of the wood TOCN-COONa films. However, the oxygen permeability of the wood TOCN-COONa films increased to 0.17 mL μm m(-2) day(-1) kPa(-1) at 50% RH, which is one of the shortcomings of hydrophilic TOCN-COONa films. |
| Databáze: | OpenAIRE |
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