Cellulose Nanofibers in Water Observed by the Quick-Freeze, Deep-Etch Replication and HAADF-STEM

Kazunori Kawasaki, Tomoki Kato, Yuka Watanabe, Koichi Uegaki, Kenichi Harashima, Kota Ogura, Minoru Hayashida and Kazuhiko Ishikawa

Abstract: To apply cellulose as an industrial resource, a novel method for pulverization of crystalline cellulose by water-jet was developed. Morphology of cellulose treated with the method was examined by electron microscopic observations. The quick-freeze, deep-etch replica technique combined with high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and electron tomography was useful to visualize the fine structures of cellulose in water. The result demonstrated that the treatment dispersed cellulose to nanofibers (20-40nm wide) which formed three-dimensional networks in water.

Key words: cellulose nanofiber, water-jet, quick-freeze deep-etch replica, HAADF-STEM, electron tomography