Functionalization of Microcrystalline Cellulose through Integrated Sodium Periodate and TEMPO/Ozone Oxidations

Abstract

Cellulose modification has been a primary focus in developing bio-based degradable functional materials. In this study, an integrated approach combining sodium periodate (NaIO₄) and TEMPO (2,2,6,6-tetramethylpiperidin-1-oxyl)-ozone oxidation process is employed to functionalize microcrystalline cellulose (MCC). The resulting materials in water-soluble and precipitate fractions were characterized to understand the influences of each oxidation method on the reaction mechanisms, structures, and physicochemical properties of the oxidized MCC samples. The results demonstrated that the combination of both methods resulted significantly in chemical structures, morphology, and surface reactivity of the samples. FTIR spectra showed an appearance of oxidized functional groups, i.e., carboxyl, ketone, and aldehydes, confirming a successful oxidation process. The use of ozone as a co-oxidant contributes positively to environmental aspects and process economics due to its availability and low cost. These findings illustrate the considerable potential of ozone utilization in improving cellulose properties for various applications. Consequently, the integrated approach offers an effective and sustainable solution for enhancing the quality and performance of cellulose, paving the way for further research and applications in the field of cellulose materials.

Keywords: Microcrystalline cellulose, TEMPO, Periodate, Ozone, Oxidation process