Structural features and water interactions of etherified xylan thin films

Soledad Peresin, Kari Kammiovirta, Harri Setälä, Tekla Tammelin (Corresponding Author)

    Research output: Contribution to journalArticleScientificpeer-review

    20 Citations (Scopus)

    Abstract

    In this paper, the model film approach was used to investigate the structural features and humidity induced changes of the etherified xylan derivatives by using surface sensitive methods. Two routes to modify the birch xylan to generate either cross-linking xylan or more hydrophobic xylan were mastered via allylation and butylation, respectively. Thin nanometer scale model films were prepared by spin-coating and the films were further treated by UV-radical treatment and heat. The structural changes and wetting behaviour of the films before and after the post-treatment procedures were studied using atomic force microscopy and water contact angle measurements. In addition, the water vapour uptake of the xylan derivative films was monitored using quartz crystal microbalance with dissipation (QCM-D) equipped with the humidity module. With the QCM-D, the mass uptake due to the water vapour binding was defined. Simultaneously the changes in the viscoelastic properties of the films when subjected to different relative humidity conditions were determined. We show that the water sensitivity and wetting behaviour of the water soluble xylan derivatives can be altered by cross-linking the film structure and through the molecular rearrangements. Cross-linking and the conformational rearrangements of the allylated xylan reduced the water vapour uptake ability approximately 80 %. Butylated xylan as being a more hydrophobic derivative showed lower ability to uptake water vapour when compared to more hydrophilic xylan derivative. This ability was even further reduced after the post-treatments mainly due to the reassembly of the hydrophobic groups.
    Original languageEnglish
    Pages (from-to)895-904
    Number of pages10
    JournalJournal of Polymers and the Environment
    Volume20
    Issue number4
    DOIs
    Publication statusPublished - 2012
    MoE publication typeA1 Journal article-refereed

      Fingerprint

    Keywords

    • Crosslinking
    • etherifield xylans
    • QCM-D with humidity module
    • water vapour uptake
    • wetting

    Cite this