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Byline: Heba. Abdelkafy, Hemat. Elsheikh, Mohamed. Kataia, Rasha. Marzouk, E. Abdeltwab, A. Atta, Fatma. El-Rahman Taher Background: This study evaluated the effect of using chitosan, nano-chitosan, and ethylenediaminetetraacetic acid (EDTA) [...]

This current work using solution-casting preparation method to create flexible polymer composite materials including titanium dioxide (TiO2) and polyvinyl alcohol (PVA). Then, using a wide beam homemade cold cathode ion generator the samples were irradiated by oxygen fluence of 4x1016, 8x1016, and 12x1016 ions.cm−2. Using EDX, contact angle and XRD techniques, the PVA/TiO2composite film successful production was evaluated. The effects of ion exposure on the optical behavior are reported using UV-Vis technique. The PVA/TiO2dispersion energy is 1.75 eV, increased to 2.21 eV, 2.66 eV, and 3.12 eV by irradiation of 4x1016, 8x1016, and 12x1016 ions.cm−2. Moreover, the refractive index (n0) of the PVA/TiO2is 1.18 increased to 1.25, 1.32, and 1.40 respectively. Moreover, the oscillation energy E0reduced from 4.24 eV for the PVA/TiO2composite to 3.84 eV, 3.64 eV, and 3.27 eV, respectively. Thus, the changes in the optical and structural alterations in PVA/TiO2films by ion irradiation, is employ for directed the treated PVA/TiO2materials in various optoelectronic.

Herein, (PPy-Ag)/PET composites, consisting of silver nanoparticles (AgNPs) and polypyrrole (PPy) coated on PET, were fabricated by the polymerization process and then the films were characterized by SEM and XRD techniques. The addition of PPy-Ag on the dielectric properties of PET were determined. The XRD proved the successful synthesis of the (PPy-Ag)/PET samples. The SEM results demonstrate the effect of Ag modified the characteristics of the composite, which confirmed the interaction of (PPy-Ag)/PET. The dielectric properties of the films in frequency of 50 Hz to 5.6 MHz were measured. The density energy was enhanced from 9.1 × 10−5for PET to 5480 × 10−5J m−3for (PPy-Ag)/PET. Moreover, the relaxation time τrdecreased from 1.7 × 10−5for PET to 2.8 × 109sec for (PPy-Ag)/PET. The obtained data confirm the incorporation of PPy-Ag by PET. This research has led to the development of novel physico-chemical properties in flexible polymeric nanocomposite films, which could be used in high-performance energy storage devices.

In this work, mixtures of polypyrrole (PPy) and iron oxide (Fe2O3) are synthesized using oxidative chemical polymerization process to create a novel flexible PET/(PPy-Fe2O3) composite films. The films were characterized by different methods as FTIR, SEM, XRD and TGA to prove the efficient manufacturing of the composite. The dielectric performance measurements were done at frequency of 20 Hz to 6 MHz for the polymer PET and the composite (PPy-Fe2O3)/PET with varying concentrations of Fe2O3. Moreover, to reveal the characteristics of the fabricated composite, the contact angle, the work of adhesion, surface energy of the composite PET/(PPy-Fe2O3) films were considerably determined. The SEM results support the deposition of PPy-Fe2O3composite on the PET surface. The water contact angle drops from 78.32° for PET to 40.11° for PET/6%(PPy-Fe2O3), while the dispersive free energy raised from 23.9 mJ m−2to 43.7 mJ m−2and the polar free energy rises from 8.9 mJ m−2to 22.3 mJ m−2. The concentration of Fe2O3increased the surface features of the samples, according to the obtained results. At frequency of 100 Hz, the dielectric constant enhanced from 18 for PET to 923 for the PET/6%(PPy-Fe2O3), and the dielectric loss improved from 24 to 9231, while the energy density improved fromm 7.9 × 10−5J/m3for PET to 408 × 10−5J m−3. The TGA results show marginal modifications in thermal stability after deposition the PPy/Fe2O3on the PET film. The obtained data showed the dielectric characteristics of the PET/(PPy-Fe2O3) were improved respect to polymer PET, to can be applied the fabricated composite in storage devices and capacitors.

This work study the impacts of argon irradiation on surface wettability of CA/PANI using home made ion source with fluences (4 × 1014, 8 × 1014, and 12 × 1014ions cm−2). The EDX, SEM and FTIR methods verified the successful fabrication of the composites. Surface wettability, contact angle, and work of adhesion were measured for the untreated and irradiated composites. Raising the ion flux from 4 × 1014ions.cm−2to 12 × 1014ions.cm−2, it decreases the contact angle of CA/PANI from 62.1° to 43.4° and increases the surface free energy from 46.7 to 63.9 mJ m−2. The results showed that the CA/PANI changed after exposed to radiation, proving that the irradiated surface properties were improved. In addition, their electrical conductivity was tested in frequency of 50 to106Hz. When subjected to 12 × 1014ions.cm−2, the conductivity rose from 1.1 × 10−8S cm−1for CA/PANI to 6.5 × 10−7S cm−1. The results showed that the irradiated CA/PANI had better electrical and surface properties, which is crucial for many devices including batteries and supercapacitors.

PVA/PANI/Ag composite materials made of silver (Ag), polyaniline (PANI), and polyvinyl alcohol (PVA) are prepared for applied in electrical devices. The structure of PVA/PANI/Ag composites was analyzed using XRD, which indicating the samples were successfully synthesized. The crystallite size of AgNPs changed from 12.1 nm to 16 nm by increasing the Ag content from 3 to 6% in the PVA/PANI blend. Moreover, in temperature range 293–353 K, the impacts of PANI as well as AgNPs on the conductivities, permittivity, as well as energy density of PVA were investigated. The conductivity of the films was enhanced with higher frequency due to charge carrier mobility. Furthermore, the density is increased from 1.96 × 10−6J m−3at 20 °C for PVA to 2.7 × 10−6for PVA/PANI/Ag. These results show the prepared PVA/PANI/AgNPs can applied in in a wide range of electronic technologies like batteries, electronic circuits, as well as super capacitors.

In this work, PVA polymeric sheets were irradiated utilizing a homemade ion beam cold cathode source for use in optoelectronics applications. The PVA films were exposed to hydrogen beams with fluence range 8 × 1017to 24 × 1017ions.cm−2. The structural and functional group characteristics of pure and treated PVA films were investigated using XRD and FTIR methods, which confirmed the success fabrication of the PVA films. In frequency of 102to 5 × 106Hz, the conductivity, electrical impedance, and dielectric modulus of untreated and treated samples were determined. The dielectric characteristics of PVA films exhibit a significant modification when subjected to a hydrogen beam. Additionally, after being exposed to 16 × 1017ions, the dielectric constant ε′ improved from 0.0078 for un-irradiated PVA to 0.0395, and conductivity changed from 8.87 × 10−11S cm−1to 3.32 × 10−10S cm−1. Moreover, the relaxation time for PVA is reduced from 28.4 × 10−5s to 8.98 × 10−5s for 8 × 1017ions.cm−2and to 3.5 × 10−5s for 24 × 1017ions.cm−2. The present study extends the potential use of the treated PVA films to a broader range of fields, including microelectronics.

This work presents comprehensive study of high density polyethylene (HDPE) and polyethylene terephthalate (PET) surface properties after exposed to 1.5, 3, 4.5 and 6 min oxygen (O2) plasma. The polymer surface structure is analyzed by Raman spectroscopy, which revealed surface restructuring modifications. The contact angle of HDPE and PET decreased gradually, and the work of adhesion is improved with O2plasma. The water contact angle is reduced from 61.6° to 36.3° for HDPE and from 72.4° to 37.5° for PET by increasing plasma time from 1.5 to 6 min. The surface free energy is enhanced from 27.8 mJ m−2to 69.0 mJ m−2for HDPE and from 29.8 mJ m−2to 67.2 mJ m−2for PET, when the plasma time increased from 0 to 6 min. The polar groups significantly reduced the hydrophobicity of the irradiated films, and consequently the surface wettability is improved. The results showed observed improvement in surface properties of HDPE and PET polymeric films to be use in different applications such as printings, coatings and optoelectronics.

In the present paper, the surface properties of polydimethylsiloxane (PDMS) films were modified by exposure to argon (Ar) ion beam with a fluence of 0.25 × 1018ion.cm−2to 1 × 1018ion.cm−2. The pristine and irradiated PDMS films were examined through scanning electron microscopy (SEM) and contact angle (CA) measurements. The SEM of irradiated films reveals a modification in the morphology due to ion irradiation. On the other hand, the CA data showed an enhancement in the adhesion wettability due to the formation of hydrophilic functional groups. In addition, silver nanoparticles (AgNPs) were deposited on the modified PDMS substrate using ion beam-sputtering technique. Then, PDMS and Ag/PDMS films were characterized using X-ray diffraction (XRD (and UV/Vis optical spectroscopy. XRD showed a successful deposition of AgNPs on PDMS substrate, while the optical transmittance intensity is reduced for Ag/PDMS than PDMS, and the optical band gap Egis decreased from 5.22 eV for PDMS to 5.05 eV for Ag/PDMS. The results illustrated significant modifications in PDMS due to AgNPs deposition.