2007/07/13 by Tsuguyuki Saito, Satoshi Kimura, Yoshiharu Nishiyama +1 · 2 citations
Materials Science · Engineering · #Advanced Cellulose Research Studies #Electrospun Nanofibers in Biomedical Applications #Lignin and Wood Chemistry
paper · doi:10.1021/bm0703970
openalex publication_date 2007/07/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
Never-dried and once-dried hardwood celluloses were oxidized by a 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated system, and highly crystalline and individualized cellulose nanofibers, dispersed in water, were prepared by mechanical treatment of the oxidized cellulose/water slurries. When carboxylate contents formed from the primary hydroxyl groups of the celluloses reached approximately 1.5 mmol/g, the oxidized cellulose/water slurries were mostly converted to transparent and highly viscous dispersions by mechanical treatment. Transmission electron microscopic observation showed that the dispersions consisted of individualized cellulose nanofibers 3-4 nm in width and a few microns in length. No intrinsic differences between never-dried and once-dried celluloses were found for preparing the dispersion, as long as carboxylate contents in the TEMPO-oxidized celluloses reached approximately 1.5 mmol/g. Changes in viscosity of the dispersions during the mechanical treatment corresponded with those in the dispersed states of the cellulose nanofibers in water.