This study was designed for the fabrication, characterization, and optimization of electrospinning blending three natural biopolymers including gelatin:chitosan:sodium alginate (G:CS:SA) solutions. Series of pure gelatin, 80:10:10, 60:20:20, 40:30:30, and 20:40:40 ratios of blends (G:CS:SA) were dissolved in aqueous acetic acid. The effects of solution property parameters blends were investigated through evaluation of the electrical conductivity, viscosity, and surface tension. The morphological properties of bio-nanofibers were studied using field-emission scanning electron microscopy to determine the diameter, bead formation, and the nanofiber distribution. The results showed that the increase in the percentage ratio of CS with SA higher than 40 % in G:CS:SA caused a decrease in polymer viscosity, average fiber diameter, and bead formation. The nanofibers produced from blending ratio 80:10:10 G:CS:SA had a uniformity and low numbers of bead formation. On the other hand, X-ray diffraction showed a higher crystallinity percentage and crystalline size for the aforementioned ratio; in addition, the Fourier-transform infrared showed interactions among the molecules of G, CS, and SA in nanofibers.

In this study, both polyvinyl chloride (PVC) and polyacrylonitrile (PAN) were dissolved in dimethyl formaldehyde (DMF) with 8 wt. % concentrations at 25 : 75, 50 : 50, and 75 : 25 of PVC: PAN blending. For the investigation of the homogeneity and compatibility of mixture polymer solutions, it is examined by rheological properties such as viscosity, shear stress, shear rate, and calculation of the flow behavior index, while the investigation of the stability and high density of nanofibers without beads used field-emission scanning electron microscopy (FE-SEM), Fourier transform near-infrared spectroscopy (FT-NIR), X-ray diffraction (XRD), and differential scanning calorimetry-thermogravimetric analysis (DSC-TGA). The results show that blending of PAN with PVC leads to improving of the electro spun ability of PVC with more stability, and the mean nanofiber diameter was at 25 : 75 PVC: PAN. Moreover, mechanical properties are ultimate tensile strength and modulus of elasticity decreasing with decreasing the blending ration from pure PVC to 75 : 25 PVC: PAN nanofibers by 71% and 83%, respectively, while the elongation at break increases by 79%, and decomposition temperatures decreased from 451.96 to 345.38°C when changing the PVC content from pure PVC to 25 : 75 PVC: PAN. On the other hand, changing of the nanofiber behavior from hydrophobicity to hydrophilic increased the PAN content in PVC: PAN blends. Furthermore, the low interaction between the chains of polymers and the crystallinity (%) and crystalline size (nm) of blend nanofibers slightly decreased compared to the pure polymers. According to all tests, the 25: 75 PVC: PAN was the best blending ratio, which gave a more stable nanofiber produced at low concentrations and more compatible between the PVC and PAN.

This work attempts to study the effects of the addition of graphene nanoplatelets (xGNP) on the rheology properties of new version of polyurethane copolymer with 1,5 pentane diol as chain extender , containing a high amount of hard blocks. Two- step polymerisation was employed to synthesise this kind of polymer. The thermal and electrical conductivity of this copolymer was also investigated. Meanwhile, the rheology response has been analysed by measuring the viscosity It was found that the viscosity increases by 68% and 2 × 10⁵% at loadings of 0.5 wt.% and 15 wt.% of xGNP, respectively, compared with that of neat polyurethane copolymer. This means that the melt viscoelastic behaviour of highly rigid polyurethane copolymer (HRPUC) is influenced by the presence of xGNP contents, transforming the behaviour of nanocomposite from liquid-like to solid-like. This result was attributed to the network formation and interaction between hard segments of the HRPUC structure and xGNP due to strong shear thinning behaviour. In addition, the thermal conductivity of HRPUC increases to 0.97 W m⁻¹.k (410%), electricity conductivity rose to 10²s m⁻¹(1000%). SEM morphology images showed overall dispersion of xGNP in the HRPUC, implying a reduction in the interspacing of flakes with increasing xGNP concentration. Further investigation into HRPUC morphology and its nanocomposites was conducted using the TEM method, illustrating that the xGNP stacking resulted from poor ability to disperse at greater loadings of xGNP.

This study clarifies the important role of nanofibers produced from polyacrylonitrile after reinforcement with iron nanoparticles (γ-Fe2O3), to expand the applications of these fibers and to combine their ability to remove Nickel (II) from aqueous solutions with their ability to remove pollutants such as total suspended solids, total nitrogen, chemical oxygen demand, and cyanide as well as killing the bacteria in wastewater. The results of the absorption of Nickel (II) after treatment of the aqueous solution were obtained by an atomic absorption spectrometer type (AAs-7000) and a spectrometer type (Hach DR2800) after treating samples of wastewater obtained pollutant absorption results. The adsorption kinetic parameters results for Nickle (II) proved that the rates of increase in the maximum absorption capacity were 43.27 to 133.5 and from 74.63 to 178.571 mg/g when increasing the initial concentration (10-50 mg/L) for first and second order models. The pH, contact time, electrical conductivity, and initial concentration are good indicators of adsorption efficiency of Nickel (II), the high removal efficiency was 23.96 % at low initial concentration. Also, an increase the reduction rate and increased in TN: TP ratio were significant to increase the reduction rate of the total bacteria up 90 % at 8 hours.

In engineering applications, especially ultrafiltration (UF) applications, it is very important to use polyacrylonitrile (PAN) and poly (vinylidene fluoride) (PVDF) nanofiber membranes. In this study, membrane nanofibers made of pure PAN, PVDF: PAN blends, and pure PVDF (M1, M2, M3, M4, M5, and M6), were produced by the electrospinning technique with different contents of PVDF in each blend. The prepared membranes were characterized by field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), contact angle measurements, x-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectrophotometry, and differential scanning calorimetry-thermogravimetric analysis (DSC-TGA). In terms of the physical properties, the viscosity of the membranes increased with an increase in the content of PVDF in the blends compared with the viscosity of the pure polymer solutions. This led to increases in nanofiber diameter, pore size, and porosity by 261.664%, 875.107%, and 114.41%, respectively, when the content of PVDF increased from 20% (M2) to 80% (M5); this was also accompanied by an increase in the surface wettability of the membrane depending on its contact angle. In addition, the thermal properties and crystallinity of PAN improved after increasing the PVDF content from 20% (M2) to 60% (M4). Moreover, the filtration efficiency of the membranes was measured to determine the per cent reduction in pure water flux, reduction in mean depth (RMD) before and after using dry milk protein, the flux recovery ratio and porosity, giving values of 15.68%, 82.51%, 84.32%, and 67.79%, respectively, for the M4 membrane.