Effect of nanographene oxide and ionizing radiation on mechanical, physical, and thermal properties of composites based on high‐density polyethylene and waste bagasse fibers

Self Cite

In the present research, waste polyethylene (WPE)/Bi2O3 composites have been investigated as lightweight, inexpensive, and nontoxic lead‐free γ‐ray shielding materials. Different WPE‐based composites were prepared with varying concentrations of Bi2O3 (30 and 40 phr). The effect of adding ZnO and CuO nanoparticles (NPs) inside the WPE/Bi2O3 (30) matrix was studied by incorporating 10 phr of NPs inside it. The nanocomposites' structural, thermal, and mechanical properties and competence in shielding against γ‐radiation are studied. The outcomes revealed that the mechanical properties of the pristine WPE were enhanced after incorporating Bi2O3 by 30 phr, and then it worsened after increasing the Bi2O3 ratio to 40 phr. In contrast, better mechanical properties were obtained for those composites with NPs, where the maximum tensile strength (16.2 MPa) was recorded for the WPE/Bi2O3/CuO composite (higher than WPE by 47.27%). Numbers of parameters like μm, HVL (half‐value layer), TVL (tenth value layer), RPE%, and percentage of heaviness can denote the efficiency of shielding properties of composites at 662 KeV from 137Cs point source. It was found that μm and RPE% reach the maximum value for WPE/Bi2O3 (40 phr). Adding NPs decreases μm of WPE/Bi2O3 (30) slightly.Highlights Composites based on waste polyethylene (WPE)/Bi2O3 (30 and 40 phr) were fabricated. Nano CuO and ZnO improved the mechanical properties of WPE/Bi2O3 (30). WPE/Bi2O3 (40) composites show the best shielding characteristics. Nano CuO and ZnO slightly decreased μm of WPE/Bi2O3 (30).

Synthesis and characterization of waste polyethylene/Bi₂O₃ composites reinforced with CuO/ZnO nanoparticles as sustainable radiation shielding materials

Awad,

Raslan,

Abou‐Laila

et al. 2024

Self Cite

Evaluation of composites based on virgin rubber/devulcanized rubber reinforced with chemically and radiation activated polyurethane scrap for possible applications

Abdel‐Hakim,

Awad,

El‐Nemr

2024

Self Cite

Reusing industrial waste is one of the new tactics being used to fight the dumping of solid waste for environmental protection. In the current work, the waste polyurethane (WPU) was ground to a fine powder and used for reinforcement of devulcanized waste rubber/styrene butadiene rubber (DWR/SBR) blends. DWR/SBR/WPU composites were prepared using (0, 3, 6, 9, 15, 30) phr (parts per hundred of rubber) of WPU. It was hypothesized that the treatment of WPU with trimethylolpropane triacrylate (TMPTMA) and irradiated at 10 kGy would improve its compatibility with the DWR/SBR blend and, consequently, its reinforcement efficacy. The incorporation of 30 phr of treated WPU (TWPU) improved the tensile strength (TS) by 47.7% and 8.6% compared to neat DWR/SBR and composites containing 30 phr of untreated WPU (UWPU). In addition, the incorporation of TWPU improved other mechanical characteristics such as tear strength, hardness, and abrasion resistance. As a result of increasing polarity and cross‐link density within the DWR/SBR blend after the addition of polar WPU, the resistance to motor oil was improved. The outcomes are encouraging from the standpoint of the circular economy and help produce high‐performing, reasonably priced DWR/SBR composites for a range of industrial uses, especially in the floor tiles application.Highlights Waste polyurethane (WPU) was activated using gamma irradiation in the presence of TMPTMA. The treatment of WPU improved its compatibility with DWR/SBR blend. The impact of WPU treatment on the properties of DWR/SBR blend was investigated. TWPU improved the mechanical properties of DWR/SBR blend more than UWPU. TWPU increased the motor oil resistance of DWR/SBR blend more than UWPU.

Modulating structural, dielectrical and optical properties of PVA/methylcellulose/WO₃ nanocomposites for energy storage and optoelectronics applications

Aldosari,

Atta,

Henaish

et al. 2024

In this study, different polyvinyl alcohol (PVA)/methylcellulose/WO3 nanocomposites with composition of xPVA‐(100‐x) Methylcellulose (MC)‐2WO3 (where x = 100, 80, 60, 40, 20, and 0 wt%) were prepared successfully by solution casting technique. WO3 nanoparticles were introduced with 2 wt% to enhance the dielectric performance of the PVA/MC blend. The effect of changing PVA/MC weight ratios inside the nanocomposites on the structural, optical, and dielectric properties were studied by X‐ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), UV–VIS, and dielectric relaxation spectroscopy. The intensity of the PVA peak was altered randomly with varying MC ratios in the nanocomposites, which indicated disruption of the crystalline phase of PVA. Among nanocomposites, 20PVA‐80MC‐2WO3 showed the highest electrical conductivity, highest dielectric constant, longest relaxation time, and the lowest optical energy band gap due to the increased amorphous phase and disorders. In contrast, 60PVA‐40MC‐2WO3 exhibits the lowest dielectric constant and lowest conductivity, because of its high crystallinity. The decrease in the real part of impedance (Z′) value was seen in samples containing both PVA and MC polymers compared with that containing one polymer species, which attributed to the rise in the proportion of amorphous regions, leading to increased mobility of the polymer chains. Nyquist plots of nanocomposites showed angled spike and semicircle combinations, which are the typical characteristics of ionic conducting materials. Our results show that nanocomposites' PVA/MC ratio may be adjusted for many applications like energy storage, radiofrequency, and optoelectronics.