Effect of Silver Doped Zinc Oxide as Nanofiller for the Development of Biopolymer Nanocomposites from Chitin and Cashew Gum

Nanocomposites based on chitin (CT) and cashew gum (CG) with different concentrations of silver doped zinc oxide nanoparticles (Ag-ZnO) were prepared and characterized by FTIR, UV, XRD, TEM, SEM, DSC, TGA, electrical conductivity measurements. FTIR spectra showed that the characteristic absorption band of the blend was shifted to a higher frequency in nanocomposites, indicating the intermolecular interaction between the blend and nanoparticles. The change in the UV absorption of nanocomposites relative to that of pure blend indicated the successful encapsulation of crystalline metal oxide nanoparticles in the blend matrix. XRD patterns showed that the diffraction peak of the composites were shifted near to the metal oxide peak which indicated that the surface of Ag-ZnO was perpendicular to CT/CG and changed from a semi-crystalline nature to a crystalline structure. The morphological analysis using SEM and TEM showed a uniform attachment of nanoparticles within the CT/CG blend. DSC analysis showed the increased glass transition temperature by the addition of nanoparticles. Thermal stability of nanocomposites was higher than the blend and thermal stability increased with an increase in the content of nanoparticles. The different electrical properties such as AC conductivity and dielectric behaviour of the composites were increased with an increased loading of nanoparticles.