The influence of wet/dry treatment on pore structure-the correlation of pore parameters, water retention and moisture regain values

• Published in: Carbohydrate polymers 2004-08, Vol.57 (1), p.39-44
• Main Authors: Kongdee, A., Bechtold, T., Burtscher, E., Scheinecker, M.
• Format: Article
• Language: English
• Subjects: Applied sciences; Exact sciences and technology; Fibers and threads; Forms of application and semi-finished materials; Inverse size exclusion chromatography; Moisture regain; Polymer industry, paints, wood; Regenerated cellulose fibres; Structural change; Technology of polymers; Water retention; Wet/dry treatment
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2004.03.025

Three types of regenerated cellulosic fibres, normal lyocell (CLY1), crosslinked lyocell (CLY2 and CLY3), and micromodal (μCMD) were treated with five two-stage cycles comprised of wetting in water at 40 °C for 6 h, and drying at 105 °C for 6 h. The resulting changes in fibre pore characteristics were then estimated with Inverse Size Exclusion Chromatography, water retention values (WRV), and moisture regain values (MRV). Reductions in fibre pore volumes after wet/dry treatments were observed to the extents of 20, 13, 18, and 0% in CLY1, CLY2, CLY3 and μCMD, respectively. Corresponding reductions were also observed in water retention and moisture regain after the treatments. WRVs decreased by 21, 28, 24 and 14%, and MRVs decreased by 48, 43, 34 and 40% in CLY1, CLY2, CLY3 and μCMD, respectively. The changes observed in pore characteristics, WRVs and MRVs are attributed to changes that occur in the microstructures of fibres. It is proposed that structural rearrangements occur in fibres during repetitive wetting and drying that leads to decreased water sorption.