Fast and highly efficient acetylation of xylans in ionic liquid systems
Artikel i vetenskaplig tidskrift, 2013

In this study high molecular weight pure rye arabinoxylan and spruce arabinoglucuronoxylan were acetylated in ionic liquid (IL) systems. Two different ILs were used in our study. In both IL, using optimized procedures, it was possible to achieve acetylation within 5 min. The first system involved direct dissolution into 1-ethyl-3-methylimidazolium dimethylphosphate ([emim][Me2PO4]), followed by addition of acetyl chloride/pyridine (AcCl/Pyr) and additional chloroform (CHCl3), as co-solvent. The other system involved direct dissolution into the novel protic IL 1,5-diazabicyclo[4.3.0]non-5-enium acetate ([DBNH][OAc]), followed by acetic anhydride/1,5-diazabicyclo[4.3.0]non-5-ene (Ac2O/DBN) and no co-solvent added. The full acetyl substitution of the xylans was confirmed by FT IR and H-1 NMR. The acetylated xylans maintained a high molecular weight, which was confirmed by gel permeation chromatography. The products were soluble in CHCl3 and dimethyl carbonate, which is considered as a 'green' reagent or solvent. This allowed for the casting of the materials into clear transparent films, opening opportunity for further processing and evaluation of these materials.

Spruce

wood

wheat-straw hemicelluloses

arabinoxylans

solvents

oxygen barrier films

Acetylation

derivatives

Ionic liquid

anhydride

dissolution

Xylan

Rye

cellulose

nmr

Författare

Agnes Stépán

Chalmers, Kemi- och bioteknik, Polymerteknologi

A. W. T. King

Helsingin Yliopisto

T. Kakko

Helsingin Yliopisto

Guillermo Toriz Gonzalez

Chalmers, Kemi- och bioteknik, Polymerteknologi

I. Kilpelainen

Helsingin Yliopisto

Paul Gatenholm

Chalmers, Kemi- och bioteknik, Polymerteknologi

Wallenberg Wood Science Center (WWSC)

Cellulose

0969-0239 (ISSN)

Vol. 20 2813-2824

Ämneskategorier

Pappers-, massa- och fiberteknik

Textil-, gummi- och polymermaterial

DOI

10.1007/s10570-013-0028-y