Fabricate of one-dimensional structure poly (vinyl alcohol)- polyethylene glycol: calcium fluoride nanocomposites via electrospinning technique: characterization and antibacterial application

The one-dimensional structure preparation by electrospinning method is one of the most important especially since it can get fine diameters of fibers. Poly (vinyl alcohol) and (PVA)/polyethylene glycol (PEG) were mixed to get the blend and doped with different ratios (0.001, 0.002, 0.003) wt.% of calcium fluoride (CaF2) to get nanocomposite were fabricated using the electrospinning method at RT and voltage of 23 kV. Structural and optical properties were studied and the antibacterial activity was examined. The result of SEM analysis showed that the polymer blend and doped samples produced a random distribution with fine fibers at an average diameter range before CaF2 addition to be 68.97 nm and after CaF2 addition for each sample to be 45.76, 68.71, and 98.45 nm with a smooth surface. XRD analysis confirmed the existence of semi-crystalline PVA and PEG aggregates, and the CaF2 cubic crystalline phase appears when an additive of CaF2 nanoparticles up to 0.003 g. Absorbance spectra were recorded in the wavelength range of (200-800) nm. Absorption increased by two times when doping of CaF2 increased to 0.003 wt.%. The optical energy gap of fabricated films decreased with increasing CaF2 nanoparticles from (3.6-3.3) eV, while the refractive index increased. Increasing the content of NPs for the (PVA-PEG:CaF2) nanofibers mixture leads to an increase in the diameter of the inhibition zone for Escherichia coli for antibacterial activity.