Improving the thermal stability of different types of xylan by acetylation

Danila Morais de Carvalho; Jennie Berglund; Célia Marchand; Mikael E Lindström; Francisco Vilaplana; Olena Sevastyanova

doi:10.1016/j.carbpol.2019.05.063

Improving the thermal stability of different types of xylan by acetylation

Carbohydr Polym. 2019 Sep 15:220:132-140. doi: 10.1016/j.carbpol.2019.05.063. Epub 2019 May 24.

Authors

Danila Morais de Carvalho¹, Jennie Berglund², Célia Marchand³, Mikael E Lindström⁴, Francisco Vilaplana⁵, Olena Sevastyanova⁶

Affiliations

¹ Department of Fibre and Polymer Technology, KTH, Royal Institute of Technology, SE-100 44 Stockholm, Sweden; Wallenberg Wood Science Center, Department of Fibre and Polymer Technology, KTH, Royal Institute of Technology, SE-100 44 Stockholm, Sweden; Department of Food and Nutrition, University of Helsinki, FI-000 14 Helsinki, Finland. Electronic address: dmdc@kth.se.
² Wallenberg Wood Science Center, Department of Fibre and Polymer Technology, KTH, Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
³ Department of Fibre and Polymer Technology, KTH, Royal Institute of Technology, SE-100 44 Stockholm, Sweden; Grenoble INP-Pagora, Graduate School of Engineering in Paper, Print Media and Biomaterials, 38402 Grenoble, France.
⁴ Department of Fibre and Polymer Technology, KTH, Royal Institute of Technology, SE-100 44 Stockholm, Sweden; Wallenberg Wood Science Center, Department of Fibre and Polymer Technology, KTH, Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
⁵ Wallenberg Wood Science Center, Department of Fibre and Polymer Technology, KTH, Royal Institute of Technology, SE-100 44 Stockholm, Sweden; Division of Glycoscience, Department of Chemistry, KTH, Royal Institute of Technology, AlbaNova University Center, SE-106 91 Stockholm, Sweden.
⁶ Department of Fibre and Polymer Technology, KTH, Royal Institute of Technology, SE-100 44 Stockholm, Sweden; Wallenberg Wood Science Center, Department of Fibre and Polymer Technology, KTH, Royal Institute of Technology, SE-100 44 Stockholm, Sweden. Electronic address: olena@kth.se.

PMID: 31196532
DOI: 10.1016/j.carbpol.2019.05.063

Abstract

The impact of various degrees of acetylation on improving the thermal stability of xylan isolated from different botanical source has been studied; methylglucuronoxylan from birch and eucalyptus, arabinoglucuronoxylan from spruce and glucuronoarabinoxylan from sugarcane bagasse and straw. The lower molecular weight of non- acetylated methylglucuronoxylan (17.7-23.7 kDa) and arabinoglucuronoxylan (16.8 kDa) meant that they were more soluble in water than glucuronoarabinoxylan (43.0-47.0 kDa). The temperature at the onset of degradation increased by 17-61 °C and by 75-145 °C for low and high acetylated xylans respectively, as a result of acetylation. A glass transition temperature in the range of 121-132 °C was observed for the samples non-acetylated and acetylated at low degree of acetylation (0.0-0.6). The acetylation to higher degrees (1.4-1.8) increased the glass transition temperature of the samples to 189-206 °C. Acetylation proved to be an efficient method for functionalization of the xylan to increase the thermal stability.

Keywords: Acetylation; Hardwood; Molecular weight; Softwood; Sugarcane residues.