Sorption properties of TEMPO-oxidized natural and man-made cellulose fibers

• Published in: Carbohydrate polymers 2009-07, Vol.77 (4), p.791-798
• Main Authors: Praskalo, Jovana, Kostic, Mirjana, Potthast, Antje, Popov, Gordana, Pejic, Biljana, Skundric, Petar
• Format: Article
• Language: English
• Subjects: Applied sciences; Cellulose and derivatives; Cellulose fibers; cellulosic fibers; chemical modification; Cotton; Exact sciences and technology; fiber modification; iodine; Lyocell; lyocell fibers; natural fibers; Natural polymers; oxidation; Physicochemistry of polymers; sorption; Sorption properties; synthetic fibers; TEMPO-mediated oxidation; water; wood pulp
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2009.02.028

Cotton and lyocell fibers were oxidized with sodium hypochlorite and catalytic amount of sodium bromide and 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO), under various conditions. Water-insoluble fractions, collected after TEMPO-mediated oxidation, were analyzed and characterized in terms of weight loss, aldehyde and carboxyl contents, and sorption properties. Aldehyde and carboxyl groups were introduced into the oxidized cotton up to 0.321 and 0.795 mmol/g, and into the oxidized lyocell up to 0.634 and 0.7 mmol/g, respectively, where weight loss was generally lower than 12% for cotton and 27% for lyocell. Oxidized cotton and lyocell were shown to exhibit 1.55 and 2.28 times higher moisture sorption than the original fibers, respectively, and water retention values up to about 85% for cotton and 335% for lyocell, while iodine sorption values of oxidized fibers were lower up to 35% for cotton and up to 18% for lyocell than the original fibers.