Development of high strength, thermal resistant and electrical properties of polyindole/carboxymethyl chitosan/alumina blend nanocomposites for flexible energy storage applications

In order to rectify and overcome environmental perturbations and crises, researchers have recently been developing environmentally friendly materials in various sectors. The present work aims at the synthesis, characterization and properties of conductive polymer blend nanocomposites based on polyindole (PIN) and carboxymethyl chitosan (CMCS) with various concentrations of alumina (Al₂O₃) nanoparticles. The FTIR measurement reveals the distinct absorption peaks of Al₂O₃ in the PIN/CMCS blend. The minimum optical bandgap energy was observed for 10 wt% Al₂O₃ nanoparticle loaded blend nanocomposite. The presence of Al₂O₃ nanoparticles in the blend was confirmed by the change in intensity and transformation in XRD of the pure blend. SEM unveiled the improved dispersion of Al₂O₃ nanofillers within the polymer blend matrix. TEM structural evaluations of the compounds revealed the uniform dispersion of alumina at lower concentrations, transitioning into an increased degree of particle clustering at higher loadings. Thermogravimetric studies show that the addition of Al₂O₃ improved the thermal stability of the conductive polymer blend nanocomposite. The AC electric conductivity was improved considerably with increasing temperature and the inclusion of Al₂O₃. The mobilization energy of AC conductivity reduces with a rise in temperature. The mechanical strength and surface hardness of the PIN/CMCS/Al₂O₃ composites were greatly boosted by the bonding of Al₂O₃ with the conductive blend. This conductive polymer blend nanocomposite material is excellent for electronic components and bendable dielectric circuits due to improvements in optical qualities, thermal stability and electrical performance.