Thin films of polyvinyl alcohol (PVA) loaded with various concentrations of (f-MWCNTs) were prepared via the regular casting method. The physicochemical characteristics of pure and PVA/f-MWCNTs films were investigated with various techniques; X-ray diffractometer (XRD), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), UV-visible spectroscopy (UV-Vis), and thermogravimetric analysis (TGA). Moreover, the impact of loading ratios of f-MWCNTs on the dielectric constant and AC conductivity of the PVA/f-MWCNTs nanocomposite film was examined. XRD results suggest a possible improvement in the crystallinity of the PVA/f-MWCNTs composite film compared to a pristine one. Also, FTIR and XPS results confirm the formation of a hydrogen bond between PVA chains and f-MWCNTs. The optical band gaps of the PVA/f-MWCNTs composite film decrease, while the optical conductivity (σopt), dielectric constant (έ), and AC conductivity increase with increasing wt% of f-MWCNTs in the PVA matrix. Further, the thermal stability of PVA/f-MWCNTs films improved in comparison with that of PVA film.

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The influence of N plasma on the antibacterial properties of polystyrene/fullerene (C/PS) nanocomposite films with two concentrations is investigated. A comparison is made between the surface characteristics of the films before and after plasma irradiation for different time intervals. The alterations induced on the surface of the films after treatment are analyzed by contact angle and surface energy measurements, FTIR spectroscopy, and atomic force microscopy. The antibacterial properties, growth, biofilm formation, and adhesion of the nanocomposite films against two multidrug-resistant bacterial strains, Staphylococcus aureus KT337489 and Pseudomonas aeruginosa KT337488, are investigated before and after plasma irradiation. The results indicate that P. aeruginosa is more sensitive to treatment than S. aureus as well as an enhancement of the anti-adhesion of both strains to treated surfaces through exposure.

The aim of this study is to analyze the relation between the reaction rate coefficients, hence the production of active species, and the gas mixing ratio in a comparative way between Ar/N 2 and He/N 2 gaseous mixtures. The Ar and He contributions ranged from 0 to 100 % at a total gas pressure of 0.4 Torr and a reduced electric field E/N of 610 Td. Langmuir probe is employed to measure electron temperature. The results showed that adding Ar to N 2 plasma reduced both the discharge operating voltage and the electron temperature. However, an opposite action is obtained on Adding He. Also, Ar can induce the dissociation of molecular nitrogen and increase the production of nitrogen atoms, however it has an insignificant effect on the nitrogen ionization mechanism. On the other hand, He addition enhances the production of , N + and N-atoms through ionization, ionization dissociation and dissociative reaction, however it has a decreasing effect on the dissociative recombination mechanism

Films of Polymethylmethacrylate with copper nanofiller were prepared and treated with low temperature oxygen DC glow discharge plasma. FTIR spectroscopy, AFM, water contact angle (WCA) measurements and UV-Vis spectroscopy were used to detect the produced chemical, morphological and optical changes as a function of plasma treatment time. The FTIR spectra, showed a decreasing value of the main characterizing signals of the composite films in addition to the creation of an oxygen containing functional group. The surface morphology of the treated samples was altered according to the increased values of the average surface roughness, obtained from the AFM images. The WCA also, decreased noticeably with increasing treatment time. The UV-Vis spectroscopic analysis showed a decreasing value of the optical absorption in the wave length range 190-270 nm which is an indication to the loss of carbonyl group. The value of direct and indirect optical band gap decreased with treatment time meanwhile, values of the band tail width were significantly increased.