TEMPO-Mediated Oxidation Promotes Cellulose Dissolution in a Zincate–NaOH System at Suprazero Temperatures

Abstract

The cellulose dissolution is conducive to converting it into higher value-added cellulose products. However, conventional cellulose solvents possess several drawbacks, such as high cost and harsh reaction conditions. In this study, a new strategy that combined 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated oxidation and a zincate–NaOH system was proposed for cellulose solubilization. The results showed that TEMPO-mediated oxidation increased the hydrophilicity of cellulose, destroyed the surface and amorphous areas of the fiber, and facilitated solvent access to its crystalline regions in the subsequent treatment. Zn(OH)42– can be used as a stabilizer to prevent cellulose from agglomeration and form strong hydrogen bonds with cellulose to enhance cellulose dissolution. All-cellulose composites with antibacterial properties were prepared from cellulose using a partial dissolution method at room temperature. This preparation is simple and low cost, laying the foundation for its application in biomedicine.