Ice templated and cross-linked xylan/nanocrystalline cellulose hydrogels

  • Authors: Köhnke, Tobias; Elder, Thomas; Theliander, Hans; Ragauskas, Arthur J.
  • Publication Year: 2014
  • Publication Series: Scientific Journal (JRNL)
  • Source: Carbohydrate Polymers. 100:24-30.
  • DOI: 10.1016/j.carbpol.2013.03.060

Abstract

Structured xylan-based hydrogels, reinforced with cellulose nanocrystals (CNCs), have successfully been prepared from water suspensions by cross-linking during freeze-casting. In order to induce cross-linking during the solidification/sublimation operation, xylan was first oxidized using sodium periodate to introduce dialdehydes. The oxidized xylan was then mixed with CNCs after which the suspension was frozen unidirectionally in order to control the ice crystal formation and by that the pore morphology of the material. Finally the ice crystal templates were removed by freeze-drying. During the freeze-casting process hemiacetal bonds are formed between the aldehyde groups and hydroxyl groups, either on other xylan molecules or on CNCs, which cross-links the system. The proposed cross-linking reaction was confirmed by using cross-polarization magic angle spinning (CP/MAS) nuclear magnetic resonance (NMR) spectroscopy. The pore morphology of the obtained materials was analyzed by scanning electron microscopy (SEM). The materials were also tested for compressive strength properties, both in dry and water swollen state. All together this study describes a novel combined freeze-casting/cross-linking process which enables fabrication of nanoreinforced biopolymer-based hydrogels with controlled porosity and 3-D architecture.

  • Citation: Köhnke, Tobias; Elder, Thomas; Theliander, Hans; Ragauskas, Arthur J. 2014. Ice templated and cross-linked xylan/nanocrystalline cellulose hydrogels. Carbohydrate Polymers 100, 24-30 7 p.
  • Keywords: Cellulose nanocrystals, cellulose whiskers, freeze-casting, hydrogel, xylan
  • Posted Date: September 17, 2014
  • Modified Date: May 8, 2015
  • Requesting Print Publications

    Publication requests are subject to availability. Fiscal responsibility limits the hardcopies of publications we produce and distribute. Electronic versions of publications may be downloaded, distributed and printed.

    Please make any requests at pubrequest@fs.fed.us.

    Publication Notes

    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
    • Our online publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact the SRS webmaster if you notice any errors which make this publication unusable.
    • To view this article, download the latest version of Adobe Acrobat Reader.