Incorporated melanin into PMMA/PVAc/TBAI blend for developing structural, optical, electrical and morphological features: Hybrid composite blended polymers for optoelectronic applications

The current work aims to construct melanin doped blended of poly-methyl methacrylate (PMMA), polyvinyl acetate (PVAc) and tetrabutylammonium iodide (TBAI) blended polymers to apply in different optoelectronic applications. The X-ray diffraction technique was used to explore the structure of all blends. The effect of melanin doping on the morphologies of the resulting blends was examined. The blend with a doping level of x = 0.11 showed the highest absorbance in the UVA range, while the blend with a doping level of x = 0.22 demonstrated the highest absorbance in the visible range. The minimum direct bandgap (3.61 eV) and indirect bandgap (3.2 and 2.88 eV) are obtained with an x = 0.11. The sample with a value of x = 0.27 demonstrated the highest refractive index values. When the level of melanin reached 0.27 wt%, the maximum values of the optical dielectric constant were attained. The optical conductivity values were influenced by the quantity of melanin and the range of wavelengths. The ohmic/nonohmic nature of the blends and the different conduction mechanisms at different temperatures were determined.