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In this study, the composite P(4ClAni)/CuO, which consists of Poly(4-Chloroaniline) P(4ClAni) and copper oxide (CuO) nanoparticles, was successfully synthesized utilizing a chemically oxidative polymerization approach to be applied in optoelectronics. Both FTIR and EDX analyses showed that CuO has been successfully integrated into the P(4ClAni) matrix. The SEM micrographs reveal uniform loading and distribution of CuO throughout the P(4ClAni) polymeric chains. The UV–Vis absorbance, the Urbach energy, the band edge and a number of carbon clusters were determined. The Tauc relationship was used to determine the band gaps, which revealed a decrease as the CuO concentration increased. The band gap drops from 3.84eV for P(4ClAni) to 3.09, 2.85, and 2.64eV, correspondingly for P(4ClAni)/CuO-1, P(4ClAni)/CuO-2, and P(4ClAni)/CuO-3. While, the Urbach tail is increased from 1.66eV for P(4ClAni) correspondingly to 1.81, 1.85, and 1.93eV. The results show composites made of P(4ClAni)/CuO have better optical characteristics than pure polymer P(4ClAni), suggesting that they can use these composites in optoelectronics devices.

This investigation aims to analyze the effects of electron beam irradiation on the morphological and mechanical properties of green composites synthesized using natural fibers of luffa cylindrica (LC) and biodegradable polymer poly (lactic) acid. This work aims to transform the low priced, readily available, agricultural waste product LC fiber into a high value product. The major challenge during the fabrication of natural fiber composites is the chemical bonding between hydrophilic LC fiber and hydrophobic poly lactic acid (PLA) matrix. Due to the disagreeing chemical nature of fiber and matrix, they are not compatible. The fibers are exposed to physical treatment, i.e., electron beam irradiation of different doses 0.5, 1.0, 2.0, 4.0 and 10.0 Gy using 6 MeV medical linear accelerator to increase the compatibility of LC fiber with PLA. Before irradiation, LC fibers are modified with calcium salts to explore the use of composite materials in biomedical terrain. When PLA is reinforced with irradiated LC fiber, tensile strength increases by 79.87% and flexural strength increases by 177%. Mechanical parameters generated by flexural and tensile tests of this study can be explored to have various clinical applications like bone implant, replacement of cervical cavities, etc.

In this study, different percentages of semiconducting zinc oxide nanoparticles (ZnONPs) are mixed with polyvinyl alcohol (PVA) to create flexible ZnO/PVA polymer nanocomposite films. The characteristics of the prepared films are investigated using differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The XRD pattern shows that the ZnO/PVA composite films were successfully synthesized; while the SEM images show that the ZnONPs are homogeneously dispersed in the PVA polymer chain. Moreover, the DSC indicates an improvement in the thermal stability behavior with increased of ZnONPs concentration. The electrical conductivity, dielectric properties, electric modulus behavior, and the energy density efficiency of the pristine PVA and ZnO/PVA composite films are determined using an LCR meter in the frequency range 10²–10⁶ Hz. The dielectric constant of the composite film increased from 0.185 for pristine PVA to 1.389 for 9%ZnO/PVA, and the conductivity is improved from $1.93\times 10^{-5}$ S/cm to $7.98\times 10^{-5}$ S/cm. This work would open the road for utilizing ZnO/PVA flexible nanocomposite films for wide range of applications such as batteries, super-capacitor and energy storage devices.

Polymer–metal composites with different fillers, such as nanocrystalline nickel (n-Ni), core shell n-Ni and nickel oxide (NiO)[n-Ni@NiO] were prepared under the same processing conditions with polyvinyledene fluoride matrix. The larger value of critical exponents (s and s') and percolation threshold (f_c ~ 0.30) for n-Ni@NiO composites as compared to n-Ni composites (f_c ~ 0.07) and a comparable effective dielectric constant (ε_eff ~ 300) with low loss tangent (tan δ ~ 0.1) at 100 Hz in case of percolative n-Ni@NiO composite was observed. The core shell structure [n-Ni@NiO] also shows a very high value of ε_eff ~ 6000 with tan δ ~ 8 at 40 Hz. The results have been explained by using boundary layer capacitor effect and the percolation theory. The difference in f_c and critical exponents is attributed to NiO insulating layer that gives rise to different extent of continuumness at f_c and have been explained with the help of Swiss cheese model.

In this work, PVA/NaI consisting of polyvinyl alcohol (PVA) and sodium iodine (NaI) is irradiated using argon at fluence (45×10${}^{16}$, 90×10${}^{16}$, and 135×10${}^{16}$ ion/cm²). The structure is investigated by XRD technique. The influence of argon ion is studied theoretically by SRIM/TRIM simulations. The target vacancies are recorded 46/ion, target displacements are 47/ion, and the replacements atoms are 1/ion. Also, the dielectric properties were determined in the frequency of 100 Hz to 5 MHz. With an average fluence 90×10${}^{16}$ ions/cm², electrical conductivity and dielectric constants have increased to twice their initial value. Additionally, after being exposed to an ion beam, the dielectric loss is reduced to around half of its original value. For both the control and irradiation samples, the attenuation and half layers were estimated. The dielectric characteristics of the irradiated samples were found to improve. Numerous uses, including energy storage and batteries, are rendered possible by these results.

Our prior studies of polymer composites subjected to stress have shown that a statistical distribution of acoustic emission damage events occur in multiscale and include several damage modes. Various multiscale modeling and simulation methods have been developed by others to obtain constitutive equations, which were used to link the variables between microscopic and macroscopic scales of continuum. Very limited experimental work exists to reveal physical evidence on the multiscale damage modes, and their relationship and consequential influence on performance of materials. This paper reports an innovative approach that experimentally evidences the response of damage events in different scales to the applied stress. It shows that a strong correlation exists between multiscale damage modes, and that ensemble-normalized entropy and physical evidence can be qualitatively and quantitatively used to integrate related damage modes at different scales.

Nanotechnology offers fundamentally new capabilities to architect a broad array of novel materials, composites and structures on a molecular scale. It is potentially capable of redefining the methods used for developing lighter, stronger, high-performance structures and processes with unique and nontraditional properties. This review summarizes different classes of nanocarbon-based polymer composites and their applications. Also, it highlights different ways to create smaller, cheaper, lighter and faster devices using nanocarbon-based polymer composites. The potential applications of such materials are in the fields of membrane, aviation, electronics, polymer composites, as well as the marine and transport industries. A detailed description of nanocarbon-based composite materials manufactured from PE, PP, PS, PS, PVC, PPS, ABS, PMMA, nitrile rubber, etc. is also reviewed. Some of the major applications of carbon-based polymer nanocomposites are in the tyre industry, semiconductors, and many more, which has brought about the new, developing and exciting research field called nanoscience.

Composites of poly(methyl methacrylate) (PMMA) and ${\mathrm{Sr}}_2{\mathrm{TiMnO}}_6$ (STMO) were fabricated via melt mixing followed by hot pressing technique. These were characterized using X-ray diffraction (XRD), thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), thermo mechanical analysis (TMA) and impedance analyser for their structural, thermal and dielectric properties. The coefficient of thermal expansion (CTE) was measured between 40°C and 100°C for pure PMMA is 115.2 ppm/°C, which was decreased to 78.58 ppm/°C when the STMO content was increased to 50 wt.% in PMMA. There was no difference in the glass transition ($T_g$) temperature of the PMMA polymer and their composites. However, the FTIR analysis indicated possible interaction between the PMMA and STMO. The density and the hardness were increased as the STMO content increased in the PMMA matrix. Permittivity was found to be as high as 30.9 at 100 Hz for the PMMA+STMO-50 wt.% composites, indicating the possibility of using these materials for capacitor applications. The thermal stability of polymer was enhanced by incorporation of STMO fillers.