This study aims to explore the use of knitted rag by synthesizing different grades of carboxymethyl cellulose (CMC) by applying multiple-step carboxymethylation techniques.
CMC was synthesized from knitted rag, a cellulosic waste of textile and garment industries, in aqueous ethanolic sodium hydroxide and subsequently mono-chloroacetic acid reaction medium. Low-substituted to high-substituted products were obtained from single-step to seven-step carboxymethylation of cellulose. In this way, it was possible to produce low-cost and different grades of substituted carboxymethylated cellulose. The synthesized CMC was characterized, and their physical properties were investigated. The structure of CMC and grafted CMC were investigated by Fourier transform infrared spectroscopy.
Solubility, CMC content, degree of substitution and molecular weight of CMC were increased gradually with the increase in the number of reaction steps, although fourth step attained the optimum. The cellulosic waste of knitted rag can easily be used to produce value-added products such as CMC and other cellulose derivatives, and that will ultimately reduce the pollution problems from this waste.
Grafting of prepared CMC film with methyl methacrylate monomer increased their strength, although decreased rigidity and moisture content because the incorporation of hydrophobic methyl methacrylate monomer was observed.
