Nanocomposite blend films were prepared by a simple casting method. Polyvinyl propylene (PVP) and chitosan (PVP/chitosan) were used as a based material. Different CuO nanoparticles concentrations were added to a specific blend film concentration of PVP/chitosan (80/20). The mechanism of the interaction between the blend and the nanoparticles was studied by different characterization techniques. The structure modification was confirmed by X-ray diffraction pattern due to the addition of the nanoparticles, in addition, the complexation and the miscibility between the nanoparticles and the blended composite was confirmed by UV–Vis spectroscopy and Fourier transform infrared spectroscopy is by the appearance of new peaks in the spectrum. The band gap computation and optical characteristics show that the addition of the nanoparticles decreases the crystallinity of the nanocomposites system. The findings show that the surface morphology checked by scanning electron microscopy shape and swelling rate behavior are affected by the integration of CuO nanoparticles into the polymer blend matrix. From all the results, this work has a great interest in wide bioapplications such as wound healing and food packing.