Nano-cellulosic materials: the impact of water on their dissolution in DMAc/LiCl.
The dissolution behaviour of disassociated cellulosic materials in N,N-dimethylacetamide/lithium chloride (DMAc/LiCl) was investigated. The parameters monitored were chromatographic elution profiles and recovered mass by means of gel permeation chromatography (GPC) with RI detection. In order to elucidate the impact of the disassembly on cellulosic fibres, comparative studies were performed with the non-disassociated cellulose counterparts. The importance of the presence of water was addressed by Karl Fischer titration and solvent exchange experiments. Morphological changes during the dissolution process were studied by scanning electron microscopy (SEM). Dissolution of fibrillated cellulosic materials is impeded compared to the non-fibrillated material. This is a consequence of the high-surface-area fibrils prone to retain high amounts of water. Dissolution behaviour of nano-crystalline cellulosic materials appeared to be source-dependent. Due to the absence of entangled networks, these materials retain only water bound at the surface of the nano-crystallites, indicative of both the exposed surface area and solubility. The small cellulose nano-particles extracted from dissolving pulp show lower solubility compared to the large NCC particles from cotton.
Department of Chemical and Biological Engineering/Organic Chemistry, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden. Electronic address: merima.hasani@chalmers.se.
Merima
M
Hasani
Ute
U
Henniges
Alexander
A
Idström
Lars
L
Nordstierna
Gunnar
G
Westman
Thomas
T
Rosenau
Antje
A
Potthast
D000081:Acetamides / Q000737:chemistry*; D002482:Cellulose / Q000031:analogs & derivatives / Q000737:chemistry*; D002850:Chromatography, Gel; D032561:Cotton Fiber; D007700:Kinetics; D018021:Lithium Chloride / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry*; D012995:Solubility; D014867:Water / Q000737:chemistry*
D000081:Acetamides; D014867:Water; D002482:Cellulose; D018021:Lithium Chloride; C013959:dimethylacetamide
Accessibility; Dissolution kinetics; Fibre morphology; Fibrillated cellulose; Gel permeation chromatography; Water content