Dissolution and gellation of cellulose in TBAF/DMSO solutions: The role of fluoride ions and water
Artikel i vetenskaplig tidskrift, 2009

Solutions of cellulose in a mixture of tetrabutylammonium fluoride and dimethyl sulfoxide (TBAF/DMSO) containing small and varying amounts of water were studied by nuclear magnetic resonance (NMR). By measuring the composition dependences of 19F NMR and 1H NMR chemical shifts and line widths, details on the dissolution and gelation mechanisms for cellulose in TBAF/DMSO were elucidated. Our results suggest that the strongly electronegative fluoride ions act as hydrogen bond acceptors to cellulose hydroxyl groups, thus dissolving the polymer by breaking the cellulose-cellulose hydrogen bonds and by rendering the chains an effective negative charge. It was found that the fluoride ions also interact strongly with water. Small amounts of water remove the fluoride ions from the cellulose chains and allow reformation of the cellulose-cellulose hydrogen bonds, which leads to formation of highly viscous solutions or gels even at low cellulose concentrations.

Författare

Åsa Östlund

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

Dan Lundberg

Universidade de Coimbra

Lars Nordstierna

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

Krister Holmberg

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

Magnus Nydén

SuMo Biomaterials

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

Biomacromolecules

1525-7797 (ISSN) 1526-4602 (eISSN)

Vol. 10 2401-2407

Ämneskategorier

Kemiteknik

Kemi

DOI

10.1021/bm900667q

PubMed

19642671