Performance of Boehmite Nanoparticles Reinforced Carboxymethyl Chitosan/Polyvinyl Alcohol Blend Nanocomposites Tailored Through Green Synthesis

Herein, a carboxymethyl chitosan (CMCS)/polyvinyl alcohol (PVA) biopolymer blend reinforced with various fractions of boehmite nanoparticles (AlOOH) was prepared using the green method. The impact of nanoparticles on the structural, morphological, thermal, tensile strength, conductivity, and dielectric properties of biopolymer blend nanocomposite films were thoroughly examined. Fourier transform infrared (FTIR) spectra and X-ray diffraction (XRD) patterns demonstrated the effective interaction and successful inclusion of nanoparticles in the CMCS/PVA blend matrix. The SEM and optical images showed that the filler addition altered the surface morphology of the CMCS/PVA blend. Thermogravimetric analysis (TGA) showed a significant enhancement in the thermal stability of blend with the increase in boehmite content. The glass transition and melting temperature of the blend nanocomposites were significantly increased with the addition of nanoparticles as observed from DSC. The AC conductivity and dielectric constant of 7 wt% nanocomposite films were increased by 9.7 and 2.3 times respectively, in comparison to the pure blend. Conductivity studies show a significant increase in magnitudes of the real part of dielectric permittivity and dielectric loss tangent with the filler content. The decrease in activation energy with an increase in the content of nanofillers suggested the semiconducting nature of blend nanocomposites. The mechanical properties of blend nanocomposite films showed that the addition of boehmite improved the tensile strength and hardness, whereas the elongation at break decreased. The enhanced tensile strength, thermal and electrical properties of the blend nanocomposite films enable the fabrication of biosafe flexible electronic and charge storage devices.