Synthesis of carboxymethyl cellulose from coconut fibers and its application as solid polymer electrolyte membranes

Abstract Carboxymethyl cellulose (CMC) is one of the important cellulose derivatives, and it can be developed as a host polymer for solid polymer electrolyte (SPE) membrane. This study aimed to synthesis of CMC from coconut fiber cellulose and it was applied to prepare the SPE membranes. Cellulose isolation was conducted through the delignification and bleaching process, while the CMC synthesis was conducted through alkalization and carboxymethylation treatments. SPE membranes were prepared by blending CMC with carboxymethyl chitosan (CMCh) (80/20) and mixed with various weight percentages of LiOAc at room temperature. SPE membranes characterizations were conducted using FTIR, EIS, XRD, SEM, and tensile testing. Cellulose and CMC yields were 23.1% and 65.44%, respectively. Incorporating 20 wt% LiOAc into the CMC/CMCh (80/20) SPE membrane yielded the highest ionic conductivity of 1.37 × 10 −3 S/cm.