The ability of wound dressing materials to tackle skin pathogens colonization that is associated with open wound infections is limited. Recently, green-synthesized metal oxide nanoparticles has received a lot of attention to overcome this limitation. However, titanium dioxide nanoparticles (TiO₂-NPs) exhibit exceptional antibacterial properties. In this work, several concentrations (0, 1, 3, and 5 wt.%) of TiO₂ NPs prepared using Aloe vera leaf extract were added to a blend of polyvinyl alcohol and sodium alginate (PVA:SA). This nanocomposite was designed to enhance the healing process of wounds. The interaction between the PVA:SA composite and the TiO₂ NPs was confirmed by FTIR. The thermal behavior of the nanocomposite films was investigated using DSC and TGA. The experimental results indicate that the glass transition temperatures of the nanocomposites increased by increasing the added amount of TiO₂ NPs to be 53.7 °C (1 wt.%), 55.8 °C (3 wt.%), and 60.6 °C (5 wt.%), which were consistently lower than the glass transition temperature of the matrix material (69.6 °C). The Dynamic Mechanical Analysis was examined. The nanocomposite doped with 5 wt.% of TiO₂ NPs detected a high storage modulus (21.6 × 10⁸). Based on swelling and degradation studies, the prepared PVA:SA:TiO₂ nanocomposite films have an excellent swelling rate, and the inclusion of TiO₂ NPs increases the stability of the polymeric matrix. The PVA:SA:TiO₂ nanocomposite films exhibited a superior antibacterial efficacy against Gram-positive bacteria such as Bacillus cereus and Staphylococcus aureus, compared to their effectiveness against Gram-negative bacteria like Escherichia coli. Moreover, the nanocomposite films were biocompatible with Human Skin Fibroblast. Therefore, the developed PVA:SA:TiO₂ nanocomposite films suit wound dressing applications.

In this study, a polyvinyl alcohol–sodium alginate blend, PVA:SA 3:1 (w:w), was doped with different contents of TiO₂ nanoparticles (NPs) prepared by aloe vera leaf extract to form the investigated nanocomposites. The nonlinear parameters of third-order susceptibility (χ⁽³⁾) and refractive index (n₂) were detected by using UV-Vis spectroscopy and Z-scan techniques. Some different optical parameters were also determined, including the refractive index (n), optical dielectric parameters, volume and surface energy loss functions, and some others. The best solar skin protection factor (SSPF) was investigated by 5 wt.% of TiO₂ NPs doped in PVA:SA 3:1, which was about 84.6% compared to the corresponding value of the host blend (41%). The studied nanocomposites were examined for their utility in the optical limiting of CUT-OFF laser filters utilizing a continuous He-Ne laser working at 632.2 nm. As a result, our finding demonstrated that TiO₂ NPs doped in the host blend of PVA:SA positively influences a laser light blocking for the investigated laser source. Using the estimated gap energies values, different models were used to deduce theoretical values of the linear refractive index (n). The presence of Ti peaks in the EDX spectrum confirmed the doping of TiO₂ NPs in the nanocomposites. SEM showed that the TiO₂ NPs are homogeneously dispersed through the host blend with some agglomerates. XRD spectra showed that the values of the lattice strain ε_str. detected at 2ϴ = 19.78° are 0.058, 0.055, and 0.060, corresponding to 1, 3, and 5 wt.% of TiO₂ NPs doped in the PVA:SA blend.

Composites of polyvinylchloride (PVC) embedded with different ratios of graphene nano-platelets (GnP) were prepared by the casting method. Some techniques as X-ray diffraction technique (XRD), Fourier transform infrared (FT-IR), optical microscopy, and scanning electron microscopy (SEM) were investigated. The crystalline structure of GnP dominated by increasing its ratio to 2.5 wt.% in the hosting matrix compared to the amorphous structure of the pristine PVC. Microstructural analysis showed uniform distribution of GnP in PVC with some aggregates. Also, the article represents a study of the impact of GnP loading on PVC dielectric parameters such as dielectric loss, electric modulus, ac conductivity, and their dependencies on frequency and temperature. The permittivity ε' displayed an increase in its values with increasing GnP content due to the creation of a strengthened interfacial polarization phenomenon. The values of the activation energy of the polymer were decreased with increasing the content of GnP due to the growing number of conductive networks in the composites. Therefore, GnP enhanced considerably the conductivity of the polymer composites. The mechanical strength of PVC improved with increasing GnP content in which the tensile strength increased up to ∼100%. However, Young’s modulus of PVC enhanced remarkably to be about 109%. In contrast, the elongation at break of PVC decreased by GnP reinforcement from 139.5 to 28.4% by incorporate 0.25% GnP.