Obtaining Dialdehyde Carboxymethylcellulose Through Microwave Treatment

Abstract

In this study, we investigated the process of obtaining dialdehyde carboxymethylcellulose (DCMC) with a high molecular mass and aldehyde content (AC) through periodate oxidation under microwave irradiation. We examined the effects of periodate oxidation time, sodium periodate (NaIO₄) concentration, and pH value of the solution under microwave treatment on the molecular mass, aldehyde group content, and yield of DCMC. Optimal conditions for the periodate oxidation reaction under microwave irradiation (microwave power level set at 10% or 70 W) were identified as follows: a reaction time of 10 min, oxidant concentration of 2.5% (with a molar ratio of carboxymethylcellulose to NaIO₄ of 1:1), and pH of 3.5. Under these conditions, the oxidation degree of DCMC obtained by microwave treatment was 82%, with a molecular mass of 141 kDa, a polydispersity of 1.4%, and a product yield of 70%. The obtained samples were analyzed using a variety of methods including chemical analysis, FTIR spectroscopy, thermogravimetric analysis, atomic force microscope (AFM), and nuclear magnetic resonance (NMR) spectroscopy.