Development of high‐performance biopolymer nanocomposites derived from carboxymethyl chitosan/boehmite via green synthesis

Abstract

AbstractIn this work, biopolymer nanocomposites derived from carboxymethyl chitosan (CMCS) and boehmite were prepared via an environmentally friendly technique and their structural, morphological, thermal, electrical, dielectric, and mechanical properties were investigated. The successful fabrication of carboxymethyl chitosan/boehmite nanocomposites was evident from the appearance of characteristic peaks of boehmite in FTIR and alteration in the morphology as revealed by optical and SEM micrographs. The glass transition temperature (Tg) and melting temperature (Tm) were increased as the filler content increased. The enhanced thermal stability of nanocomposites was clear from thermogravimetric results. The incorporation of boehmite nanoparticles into CMCS improved the conductivity to a semiconducting range. The dielectric constant of CMCS/boehmite nanocomposites was significantly higher compared to pure CMCS. The influence of temperature on AC conductivity, activation energy, dielectric constant and loss tangent were analyzed. Complex impedance analysis carried out by Nyquist plots and the bulk resistance showed a decreasing trend with temperature, which indicated enhanced conductivity with temperature. Tensile strength and hardness were observed to be increased with boehmite inclusion, whereas elongation at break is reduced. As a result, eco‐friendly CMCS/boehmite biopolymer nanocomposites with good thermal, mechanical, electric, and dielectric properties may be a potential green alternative for flexible electronic, charge storage, and other electrochemical devices.