Synthesis, Characterization, and Application of Carboxymethyl Cellulose from Asparagus Stalk End

Cellulose from Asparagus officinalis stalk end was extracted and synthesized to carboxymethyl cellulose (CMC(as)) using monochloroacetic acid (MCA) via carboxymethylation reaction with various sodium hydroxide (NaOH) concentrations starting from 20% to 60%. The cellulose and CMC(as) were characterized by the physical properties, Fourier Transform Infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC), Scanning electron microscopy (SEM) and X-ray diffraction (XRD). In addition, mechanical properties of CMC(as) films were also investigated. The optimum condition for producing CMC(as) was found to be 30% of NaOH concentration for the carboxymethylation reaction, which provided the highest percent yield of CMC(as) at 44.04% with the highest degree of substitution (DS) at 0.98. The melting point of CMC(as) decreased with increasing NaOH concentrations. Crystallinity of CMC(as) was significantly deformed (p < 0.05) after synthesis at a high concentration. The L* value of the CMC(as) was significantly lower at a high NaOH concentration compared to the cellulose. The highest tensile strength (44.59 MPa) was found in CMC(as) film synthesized with 40% of NaOH concentration and the highest percent elongation at break (24.99%) was obtained in CMC(as) film treated with 30% of NaOH concentration. The applications of asparagus stalk end are as biomaterials in drug delivery system, tissue engineering, coating, and food packaging.