We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
The behaviour of cationic NanoFibrillar Cellulose in aqueous media.
- Authors
Olszewska, Anna; Eronen, Paula; Johansson, Leena-Sisko; Malho, Jani-Markus; Ankerfors, Mikael; Lindström, Tom; Ruokolainen, Janne; Laine, Janne; Österberg, Monika
- Abstract
This paper deals, with cationically modified NanoFibrillar Cellulose (cat NFC), obtained by reacting a dissolving pulp with 2,3-epoxypropyl trimethylammonium chloride (EPTMAC). The cat NFC was thoroughly characterized in terms of morphology and physical properties. The dimensions of individual cellulose nanofibrils were determined by atomic force microscopy (AFM) imaging in water and in air. Fibrils as thin as 0.8-1.2 nm were observed in water. The fibril diameter changed upon drying and the average size was further quantified by image analysis. The experiments showed the importance of characterizing nanocellulosic materials in situ before drying. The fibril size in air was confirmed by cryogenic transmission electron microscopy (cryo-TEM), and it was found to be 2.6-3.0 nm. Smooth ultrathin films of cationic NFC were prepared by spincoating on silica substrates. The effect of electrolyte concentration and pH on swelling of the cationic NFC film was studied using a quartz crystal microbalance with dissipation. The results showed that at pH = 8 the cat NFC film was insensitive to electrolyte changes while at pH = 4.5, the water content of the film decreased with increasing ionic strength. The electrophoretic mobility measurements showed a cationic zeta potential for the cat NFC that decreased at increasing pH, verifying the swelling behaviour.
- Subjects
ATOMIC force microscopy; ELECTROLYTES; CELLULOSE; TRANSMISSION electron microscopy; LOW temperature engineering; SILICA; QUARTZ crystals; THIN films
- Publication
Cellulose, 2011, Vol 18, Issue 5, p1213
- ISSN
0969-0239
- Publication type
Article
- DOI
10.1007/s10570-011-9577-0