Stepwise Chemical Oxidation of Cellulose to Tricarboxycellulose: Synthesis, Structural Characterization, and Hemostatic Properties

This study reports the preparation of highly functionalized tricarboxycellulose through the sequential oxidation of cotton cellulose (CC), woven gauze (WG), and medical cotton (MC) using sodium hypochlorite (NaClO), sodium periodate (NaIO₄), and hydrogen peroxide (H₂O₂). The structural evolution of cellulose during each oxidation step was investigated by Fourier-transform infrared (FT-IR) spectroscopy, which confirmed the formation of aldehyde, carboxyl, and carboxylate groups while preserving the β-1,4-glycosidic backbone. Quantitative analysis revealed that the final tricarboxycellulose samples contained up to 53.8%, 47.5%, and 42.3% carboxyl groups for CC-, WG-, and MC-derived materials, respectively. The introduction of multiple hydrophilic functionalities significantly improved water absorption and swelling behavior. The highest swelling degree was observed for tricarboxycellulose derived from cotton cellulose, reaching 830% after 20 min, whereas samples prepared from woven gauze and medical cotton exhibited maximum swelling values of 670% and 530%, respectively. The enhanced swelling capacity was attributed to increased hydrophilicity, disruption of crystalline regions, and the formation of a more open and porous polymer network. Tricarboxycellulose prepared from cotton cellulose exhibited the most effective hemostatic activity, with a bleeding time of 69±3 sec and a blood clotting index of 55.6%, outperforming commercial oxidized cellulose powder.