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Updated: Dec 31, 2025

Artificial Thermal Ageing of Polyester Reinforced and Polyvinyl Chloride Coated Technical Fabric
Published on: January 29, 2020
Stability of TEMPO-oxidized cotton fibers during natural aging
Jovana Milanovic1, Sonja Schiehser2, Antje Potthast2
1Innovation Center of the Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11000 Belgrade, Serbia.
Abstract:
Stability of cotton fibers oxidized by the 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO)-mediated system during natural aging was monitored; the oxidized and five-year-aged fibers were characterized in terms of molecular weight distribution, quantity and distribution of functionalities, tensile strength, color difference, and yellowness index. The distribution of functionalities introduced in cotton fibers by TEMPO-mediated oxidation and subsequent aging was investigated by means of gel permeation chromatography using multiple detection and group-selective labeling. The mild TEMPO-mediated oxidation retains the molar mass of oxidized cotton, but this status is not stable during natural aging. For highly oxidized cotton, the molar mass of aged fibers is low but stable. Aged TEMPO-oxidized cotton shows a prominent discoloration and an increased yellowness index. For tensile strength, the limiting value was obtained for aged TEMPO-oxidized cotton, regardless of whether the samples had initially been oxidized with a low or high degree of oxidation.
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