A study of linear optical properties of ternary blends PVA/CMC/aloe vera biofilm for UV shielding

In this study, the solvent casting method was applied to prepare ternary blend PVA/CMC/aloe vera (60%/20%/20%) biofilms in the form of the freestanding polymeric film. The X-ray diffraction pattern revealed 93% of crystallinity of the polymeric film. The presence of functional bonding on the biofilms was analyzed by Fourier-transform infrared spectroscopy. The hardness and Young’smodulus of the prepared biofilms were examined by the nanoindentation technique. Ultraviolet (UV) absorption spectroscopy study showed that the PVA/CMC/aloe vera (PCA) blended biofilm absorption was around 280 nm, indicating a well-defined n − π* electronic transition. From the UV spectroscopy study, the absorption coefficient; Urbach energy; direct, indirect, and forbidden bandgap; optical and dielectric constant, and loss tangent of the PCA biofilm were calculated. Viscoelastic behavior of the PCA polymeric film was verified from the determined plasticity index value. The shielding efficiency of this ternary biofilm could be considered as a potential candidate for future technology-based device/packaging applications.