Novel bionanocomposites of chitosan-based blend containing LaB₆: Thermal, dielectric, and biological properties

In the presented study, a strategy that will offer alternative usage areas by strengthening the physicochemical properties of the green polymer chitosan (CS) is aimed. For this purpose, a compatible blend of CS (CS-PFPAMA) with poly 2-(4-fluorophenyl)-2-oxoethyl-2-methylprop-2-enoate (PFPAMA), a methacrylate-based synthetic polymer, was prepared by hydrothermal method. Miscibility and compatibility of the CS-PFPAMA blend were confirmed by the single glass transition temperature (T-g) determined by differential scanning calorimetry (DSC). Then, lanthanum hexaboride (LaB6) nanoparticles (NPs) prepared by the chemical method were successfully added to the CS-PFPAMA blend at different weight ratios by hydrothermal method. Morphological characterizations of CS-PFPAMA blend and produced nanocomposites were performed with Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscope, energy-dispersive X-ray spectroscopy, and atomic force microscopy, and thermal characterizations were made with thermogravimetric analysis and DSC. The thermal stability and T-g values of the obtained CS-PFPAMA blend and nanocomposites were lower than the values of the CS. However, LaB6 NPs increased the dielectric properties of the CS-PFPAMA blend. Thus, the potential use of the produced nanocomposites in electronic devices may be in question. According to the results of antibiogram tests performed by the disk diffusion method, it was determined that nanocomposites showed a serious resistance against Escherichia coli and Staphylococcus aureus pathogens. In addition, both antioxidant and oxidant properties of nanocomposites showed values close to the reference material used. The determined biological properties indicate that the CS-based nanocomposites can be used as biomaterials.