Study of electrospun PVA-based concentrations nanofibre filled with Bi2O3 or WO3 as potential x-ray shielding material

A new method in the production of protective sheets against X-ray radiation

Today, the use of X-rays in diagnosing and sometimes treating patients is inevitable. Despite the many benefits of using X-rays in medical and other sciences, the harmful effects of this radiation on human tissue should not be neglected. One of the best ways to prevent the harmful effects of X-rays on the human body is to use appropriate covers against these rays. It seems that it is necessary to find effective particles to weaken X-rays and choose a suitable substrate with high mechanical resistance to scatter particles in it. In this study, the synthesis of SnO2 nanoparticles from SnCl2.2H2O precursor and BaSO4 nanoparticles from BaCl2.2H2O precursor using neem tree extract (Azadirachta indica) as a reducing and stabilizing agent is reported. After the synthesis of nanoparticles, their structure was investigated by X-ray diffraction, scanning electron microscopy and energy dispersive X-ray analysis. Then the desired composite and nanocomposite were prepared in the polymer substrate. The sheets were prepared using an extruder and then a hot hydraulic press. The output sheets had a thickness of 1 mm. The structural characteristics of the produced sheets such as surface morphology, density of prepared composites, mechanical properties, thermal gravimetric analysis and retention of loaded particles after three times washes were investigated. The X-ray attenuation capability of each sample was evaluated by calculating the linear attenuation coefficient for each prepared sample. The results show that all sheets filled with tin and barium micro and nano particles have more X-ray attenuation capabilities than pure polymer. Among the prepared sheets, the nanocomposite prepared from low-density polyethylene (77 %) + SnO2 (10 %) + BaSO4 (10 %) + multi-walled carbon nanotubes (3 %) showed the highest X-ray attenuation.

Attenuation properties of hybrid nanocomposite film containing Ce2O, GO, and α-Al2O3 nanoparticles for high energy radiations

The use of diagnostic radiation in medical centers has spread due to the incidence of various diseases. Thus, it is essential that patients and medical staff wear protective clothing to protect themselves from their harmful effects. In the past, lead protective clothing has been used; however, the toxicity and heaviness of lead have limited the tendency to use these clothing. Recently, nanocomposites containing heavy element nanoparticles have been introduced as an alternative to lead coatings. In this study, hybrid nanocomposites containing ceria (CeO2), alumina (Al2O3), and graphene oxide (GO) nanoparticles were studied for this purpose. Ceria, alumina, and graphene oxide nanoparticles were mixed with polyethylenevinylacetate (EVA) dissolved in chloroform and casted on a glass plate to form nanocomposite films. The prepared nanoparticles and films were characterized by Fourier Transform Infrared Spectroscopy, Field Emission Scanning Electron Microscope, Thermal Gravimetric Analysis, and Energy Dispersive X-ray Analysis, and then the attenuation properties of the films against high-energy radiation (120 kV) were studied in two narrow and broad beam geometries. The results showed that hybrid films, despite having a lower percentage of nanoparticles, showed better attenuation properties, which indicated the synergistic effect of nanoparticles with different mechanisms in attenuating the radiations. The attenuation ability of these films was considerable due to their lower density compared to lead. The fabricated hybrid nanocomposite films with a suitable performance in attenuation of high-energy radiations used in therapeutic diagnostics, can be proposed as a suitable alternative to conventional lead clothing.

Investigation on Physico Chemical and X-ray Shielding Performance of Zinc Doped Nano-WO3 Epoxy Composite for Light Weight Lead Free Aprons

This report addresses a way to reduce the usage of highly toxic lead in diagnostic X-ray shielding by developing a cost-effective, eco-friendly nano-tungsten trioxide (WO₃) epoxy composite for low-weight aprons. Zinc (Zn)-doped WO₃ nanoparticles of 20 to 400 nm were synthesized by an inexpensive and scalable chemical acid-precipitation method. The prepared nanoparticles were subjected to X-ray diffraction, Raman spectroscopy, UV-visible spectroscopy, photoluminescence, high-resolution-transmission electron microscope, scanning electron microscope, and the results showed that doping plays a critical role in influencing the physico-chemical properties. The prepared nanoparticles were used as shielding material in this study, which were dispersed in a non-water soluble durable epoxy resin polymer matrix and the dispersed materials were coated over a rexine cloth using the drop-casting method. The X-ray shielding performance was evaluated by estimating the linear attenuation coefficient (μ), mass attenuation coefficient (μ_m), half value layer (HVL), and X-ray percentage of attenuation. Overall, an improvement in X-ray attenuation in the range of 40-100 kVp was observed for the undoped WO₃ nanoparticles and Zn-doped WO₃ nanoparticles, which was nearly equal to lead oxide-based aprons (reference material). At 40 kVp, the percentage of attenuation of 2% Zn doped WO₃ was 97% which was better than that of other prepared aprons. This study proves that 2% Zn doped WO₃ epoxy composite yields a better particle size distribution, μ_m, and lower HVL value and hence it can be a convenient lead free X-ray shielding apron.

UPR/Titanium dioxide nanocomposite: Preparation, characterization and application in photon/neutron shielding

The aim of present investigation is to fabricate TiO₂ reinforced novel composites as an alternate nuclear radiation shields. Unsaturated polyester resin has been reinforced by the incorporation of different weight proportions of titanium dioxide (5, 10, 15 and 20 wt%) nanoparticles. Accordingly, mass and linear attenuation coefficients (μ_m & μ), half and tenth value layers (HVL & TVL), relaxation length (λ) and effective atomic numbers (Z_eff) have been computed. Gamma ray transmission set up has been employed for the determination of experimental μ_m values and consistency of experimental outcomes has been compared with the induced results from WinXCom program and Geant4 simulation code. Moreover, discrepancy of fast neutron removal cross section with the increasing TiO₂ content in the prepared composites has been studied. Additionally, structural properties in terms of XRD, SEM, RAMAN, FTIR and mechanical properties in terms of compressive strength have been analysed. The findings of this study revealed that the addition of TiO₂ nanoparticles improved the mechanical, nuclear shielding and structural properties of composites. The best gamma ray shielding competency has been showed by the highest TiO₂ addition (20%) composite. All in all, UPR + TiO2 composites have been identified as promising alternative radiation shielding candidates owning to their cost effectiveness, ease of processing, good dispersion and lightweightness.

Evaluating the X-ray-Shielding Performance of Graphene-Oxide-Coated Nanocomposite Fabric

Exposure to ionizing radiation (IR) during diagnostic medical procedures brings certain risks, especially when experiencing recurrent exposures. The fabrication of nano-based composites, doped with different nanoparticles, have been suggested as effective shielding materials to replace conventional lead-based ones in material sciences and nanotechnology. In this study, commercially available fabrics, used to produce scrubs and gowns for clinical staff, are modified utilizing graphene oxide (GO) nanoparticles using a layer-by-layer (LBL) technique. GO was obtained from graphite through environmentally friendly technology by using a modified-improved Hummers' method without NaNO₃. Lightweight, flexible, air- and water-permeable shielding materials are produced that are wearable in all-day clinical practice. The nanoparticles are kept to a minimum at 1 wt%; however, utilizing the LBL technique they are distributed evenly along the fibers of the fabrics to achieve as much shielding effect as possible. The evaluation of samples is accomplished by simulating real-time routine clinical procedures and the radiographic programs and devices used daily. The GO-coated nanocomposite fabrics demonstrated promising results for X-ray shielding.

Shielding of Cosmic Radiation by Fibrous Materials

Cosmic radiation belongs to the challenges engineers have to deal with when further developing space travel. Besides the severe risks for humans due to high-energy particles or waves, the impact of cosmic radiation on electronics and diverse materials cannot be neglected, even in microsatellites or other unmanned spacecraft. Here, we explain the different particles or waves found in cosmic radiation and their potential impact on biological and inanimate matter. We give an overview of fiber-based shielding materials, mostly applied in the form of composites, and explain why these materials can help shielding spaceships or satellites from cosmic radiation.

LDPE/Bismuth Oxide Nanocomposite: Preparation, Characterization and Application in X-ray Shielding

Recently developed polymer-based composites could prove useful in many applications such as in radiation shielding. In this work, the potential of a bismuth oxide (Bi₂O₃) nanofiller based on an LDPE polymer was developed as lead-free X-ray radiation shielding offering the benefits of lightness, low-cost and non-toxic compared to pure lead. Three different LDPE-based composites were prepared with varying weight percentages of Bi₂O₃: 5%, 10% and 15%. The characterizations were extended to include structural properties, physical features, mechanical and thermal properties, and radiation shielding efficiency for the prepared nanocomposites. The results revealed that the incorporation of the Bi₂O₃ nanofiller into an LDPE improved the density of the composites. There was also a slight increase in the tensile strength and tensile modulus. In addition, there was a clear improvement in the efficiency of the shield when fillers were added to the LDPE polymer. The LDPE + Bi₂O₃ (15%) composite needed the lowest thickness to attenuate 50% of the incident X-rays. The LDPE + Bi₂O₃ (15%) polymer can also block around 80% of X-rays at 47.9 keV. In real practice, a thicker shield of the proposed composite materials, or a higher percentage of the filler could be employed to safely ensure the radiation is blocked.

Cellular Bi2O3/natural rubber composites for light-weight and lead-free gamma-shielding materials and their properties under gamma irradiation

This work investigated the effects of a radiation-protective filler, namely bismuth oxide (Bi2O3), and blowing agents, namely azodicarbonamide (ADC) and oxy-bis (benzene sulfonyl) hydrazide (OBSH), on gamma attenuation and the mechanical, physical, and morphological properties of cellular natural rubber (NR) composites for potential use as light-weight and lead-free gamma-shielding materials. The contents of Bi2O3 were varied from 100 to 300 and 500 parts per hundred of rubber by weight (phr) and the contents of ADC or OBSH were varied from 0 to 8 and 16 phr. The results indicated that the addition of Bi2O3 enhanced the overall gamma-shielding ability, density, tensile modulus, and hardness (Shore OO), but lowered the tensile strength and elongation at break. On the other hand, the addition of ADC or OBSH resulted in decreases in the density, linear attenuation coefficient ( μ), and overall tensile properties but an increase in the mass attenuation coefficient ( μm), with ADC producing better mechanical properties than samples with OBSH. In addition, investigations on the properties of the cellular Bi2O3/NR composites under additional 35 kGy and 70 kGy gamma irradiation revealed that the irradiated samples had increased density, tensile modulus, and hardness (Shore OO), but decreased tensile strength, elongation at break, and μm after such ageing. In conclusion, the overall results suggested that the developed cellular Bi2O3/NR composites not only had efficient and promising gamma-shielding and mechanical properties but also offered comfort and light-weight to users, which could potentially reduce discomforts caused by wearing heavier conventional radiation-protective equipment.

Electrospinning as a Versatile Method of Composite Thin Films Fabrication for Selected Applications

Today, one of the most popular nanomaterials are thin nanofibrous layers, which are used in many fields of industry, eg electronics, optics, filtration and the textile industry. They can be produced by various methods, such as drawing, template synthesis, molecular self-assembly or phase separation method, but the most common method is electrospinning from a solution or melts. Electrospinning is gaining more and more interest due to its versatility, simplicity and economy as well as the possibility of producing fibers from various types of polymeric, ceramic and metalic materials. Nanofibrous layers produced by this method are characterized by high quality and the desired physicochemical properties.