Polymer Sheets Research Articles

Behavior of Fire-damaged RC Beams After Strengthening with Various Techniques

High temperatures during a fire can significantly degrade the structural capacity of concrete. However, in many cases, it is possible to restore and strengthen fire-damaged concrete rather than completely rebuild damaged structures. The study considered two types of concrete (normal 25 MPa and high-strength 65 MPa) with two types of strengthening techniques: carbon-fiber-reinforced polymers (CFRP) sheets with different thicknesses of 1.5 and 2.5 mm and slurry-infiltrated fibrous concrete (SIFCON) jacketing with different fiber sizes of 20 and 30 mm. The numerical simulations and analyses were conducted to capture the complex behavior of fire-damaged concrete members (beams). A fire-damaged concrete beam subjected to an extreme or critical fire Exposure time (2 hours) was evaluated and modified using a finite element simulation approach. The simulation process included three stages: the first, subjecting the concrete beam to thermal loading; the second, reflecting the fire distribution map to another model of applying mechanical loading; and the third, involving the application of strengthening to the damaged model. The results showed that the strengthening using CFRP with a thickness of 2.5 improved the load-carrying capacity compared with SIFCON in both types of concrete. 200% improvement for the normal-strength concrete beam and a 136% improvement for the high-strength concrete beam, compared to the damaged beams. Doi: 10.28991/CEJ-2024-010-01-012 Full Text: PDF

Strengthening of GFRP Reinforced Concrete Slabs with Openings

Using fiber-reinforced polymer (FRP) could effectively improve the strength and endurance of reinforced concrete (RC) constructions. This study evaluated the flexural behavior of one-way concrete slabs with openings reinforced with glass fiber-reinforced polymers (GFRP) bars. It strengthened using carbon fiber-reinforced polymer (CFRP) sheets around the openings. The experimental program of this study is adopted by casting and testing four one-way concrete slabs with dimensions of (150*750*2650) mm. These slabs are divided into two groups based on whether they were strengthened or un-strengthened. For each group, two different openings (either one rectangular or two square) measured 250*500 mm and 250*250 mm, respectively, were fabricated within the pure flexural zone of the specimens. The experimental results indicate that using CFRP strips increases the maximum load capacity by around 29% for the slab with one rectangular opening and 21% for the slab with two square openings compared to the un-strengthened slabs. On the other hand, the deflection at a service load is decreased by about 35% and 37% for the slabs mentioned above, respectively.

UPGRADING OF CORROSION DAMAGED RC BEAMS USING MECHANICALLY FASTENED CFRP COMPOSITES

Reinforced Concrete structures are suffering from various deteriorations like corrosion, cracks, spalling and large deflection. These deteriorations are caused by various factors such as aging, corrosion of steel reinforcement, environmental effects and accidental impacts on the structure. There are several options available for retrofitting the structural members of the existing reinforced concrete structures. Bonding of thin steel plates is the common method of retrofitting. Nowadays, bonding using fiber reinforced polymer sheets on to the damaged members helps to increase load carrying capacity, ductility and stiffness of the damaged structure. Such technique is an effective way to improve the flexural and shear performance of the reinforced concrete damaged structure. This project mainly focused on retrofitting the corrosion damaged reinforced concrete beams using mechanically fastened carbon fiber reinforced laminates. This type of retrofitting increases the load carrying capacity of the corrosion damaged reinforced concrete beams. It also increases the flexural and fatigue strength of the damaged reinforced concrete beam. Here, the general review of literature on the reinforced concrete structures, in which FRP used for strengthening purpose, is briefly presented and they were listed in the references at the end of the report.

Effectiveness of Carbon Fiber-Reinforced Polymer Sheets for Torsional Strengthening of Reinforced Concrete Beams

Effectiveness of Carbon Fiber-Reinforced Polymer Sheets for Torsional Strengthening of Reinforced Concrete Beams

Self‐Propelling Macroscale Sheets Powered by Enzyme Pumps

AbstractNanoscale enzymes anchored to surfaces act as chemical pumps by converting chemical energy released from enzymatic reactions into spontaneous fluid flow that propels entrained nano‐ and microparticles. Enzymatic pumps are biocompatible, highly selective, and display unique substrate specificity. Utilizing these pumps to trigger self‐propelled motion on the macroscale has, however, constituted a significant challenge and thus prevented their adaptation in macroscopic fluidic devices and soft robotics. Using experiments and simulations, we herein show that enzymatic pumps can drive centimeter‐scale polymer sheets along directed linear paths and rotational trajectories. In these studies, the sheets are confined to the air/water interface. With the addition of appropriate substrate, the asymmetric enzymatic coating on the sheets induces chemically driven, buoyancy flows that controllably propel the sheet's motion on the air/water interface. The directionality and speed of the motion can be tailored by changing the pattern of the enzymatic coating, type of enzyme, and nature and concentration of the substrate. This work highlights the utility of biocompatible enzymes for generating motion in macroscale fluidic devices and robotics and indicates their potential utility for in vivo applications.

Self-Propelling Macroscale Sheets Powered by Enzyme Pumps.

Nanoscale enzymes anchored to surfaces act as chemical pumps by converting chemical energy released from enzymatic reactions into spontaneous fluid flow that propels entrained nano- and microparticles. Enzymatic pumps are biocompatible, highly selective, and display unique substrate specificity. Utilizing these pumps to trigger self-propelled motion on the macroscale has, however, constituted a significant challenge and thus prevented their adaptation in macroscopic fluidic devices and soft robotics. Using experiments and simulations, we herein show that enzymatic pumps can drive centimeter-scale polymer sheets along directed linear paths and rotational trajectories. In these studies, the sheets are confined to the air/water interface. With the addition of appropriate substrate, the asymmetric enzymatic coating on the sheets induces chemically driven, buoyancy flows that controllably propel the sheet's motion on the air/water interface. The directionality and speed of the motion can be tailored by changing the pattern of the enzymatic coating, type of enzyme, and nature and concentration of the substrate. This work highlights the utility of biocompatible enzymes for generating motion in macroscale fluidic devices and robotics and indicates their potential utility for in vivo applications.

Numerical, Theoretical, and Experimental Analysis of LVL-CFRP Sandwich Structure.

Optimization of structural elements via composition of different components is a significant scientific and practical point-of-view problem aimed at obtaining more economical and environmentally friendly solutions. This paper presents the results of a static work analysis of small-size laminated veneer lumber (LVL) beams reinforced by a Carbon Fiber Reinforced Polymer (CFRP) sheet. The nominal dimensions of LVL beams were 45 × 45 × 850 mm, and 0.333- and 0.666-mm thick reinforcement layers were used. The reinforcement was applied on opposite sides of the cross section obtaining a sandwich-type structure. An epoxy resin was used as a bonding layer. The bending tests were conducted in the so-called four-point bending static scheme in edgewise and flatwise conditions. The results of experimental tests confirmed the validity of this combination of materials. The highest load-bearing capacity was obtained for configuration, where CFRP sheets with a thickness of 0.666 mm were placed on the sides of the core, parallel to the direction of loading and the veneer's grain in the core. The increase in this case was up to a maximum of 57% compared to the core alone. The highest bending stiffness increase, 182% compared to the core alone, involves placing two layers of sheets perpendicular to the direction of loading, i.e., on the upper and lower surfaces. The presented novel sandwich structure can be competitive against traditional steel and reinforced concrete elements in civil engineering and can be utilized as beams or slabs.

Experimental and numerical evaluations of the shear performance of recycled aggregate RC beams strengthened using CFRP sheets

Conserving the ecosystems of the globe, protecting natural resources, and improving environmental conditions can all be achieved by considering sustainability in the construction industry. Recycling of building and demolition waste is one of the key approaches being investigated to accomplish this target. Twelve reinforced concrete (RC) beams were constructed for the current study in order to analyze the shear behavior of recycled aggregate concrete (RAC) beams externally strengthened with carbon fiber reinforced polymer (CFRP) sheets. The main goal of the experimental matrix was to investigate the effect of the recycled aggregate ratio on the shear response of RAC, where three recycled coarse aggregate ratios of 20%, 60%, and 100% were suggested. Additionally, the effects of incorporating two or four CFRP strengthening layers on the ultimate load, failure pattern, load-deflection responses, and stiffness of RAC beams were also investigated. Results revealed that, when different ratios of recycled aggregate estimated at 20%, 60%, and 100% were substituted for natural aggregates, the compressive strength decreased by 4.3%, 24.2%, and 40.0%, respectively, compared to natural aggregate concrete. Moreover, the RC beam that was cast utilizing 20% recycled aggregates and strengthened with four CFRP sheets exhibited the highest ultimate load among all the tested RAC beams of 84.8 kN, which was 22.9% higher than the un-strengthened specimen totally cast with natural aggregate. Furthermore, a three-dimensional (3D) non-linear finite element model (FEM) was constructed using the ABAQUS program in order to compare the effects of employing continuous CFRP sheets for the whole critical shear span length to intermittent strips that had been experimentally tested.

Design and fabrication of microfluidic devices: a cost-effective approach for high throughput production

Microdevices have been recognized as a potential platform for performing numerous biomedical analysis and diagnostic applications. However, promising and viable techniques for a cost-effective and high throughput production of microfluidic devices still remain as a challenge. This paper addresses this problem with an alternative solution for the fabrication of microfluidic devices in a simple and efficient manner. We utilized laser-assisted engraving technique to fabricate a master mold on an acrylic sheet of different thicknesses from 4 to 20mm. Low cost indigenously developed CO2 (10.6μm wavelength) laser engraving device was used for the experiments. The effect of various laser parameters such as power and speed of operation on the height of engraved structures was studied in detail. Optimal engraving results were obtained with a laser speed of 200–250mm s−1 with a spacing interval of 0.002mm at a laser power of 10–12W. Master mold of microdevice with a channel width of 100μm were produced using this technique. The replica transfer was performed by a simple imprinting method using a benchtop universal testing machine that can provide a maximum compressive load upto 1kN. The replicas were successfully generated on various thin film substrates including polymers, plastics, Whatman filter paper, teflon, vinyl sheets, copper, and aluminum sheets. The effect of load applied on the depth of the microfluidic channel was studied for the substrates such as teflon and Whatman filter paper. A load of 1kN can generate a depth of a few hundred micrometers on various substrates mentioned above. The replicas were also transferred to thermoformable PETG (polyethylene terephthalate glycol) sheets under load with an elevated temperature. The channel-imprinted PETG substrates were later sandwiched between two acrylic sheets with adhesive-coated polymer sheets and screws at the corners. Soft lithographic techniques were also performed to replicate the channel on a poly dimethyl siloxane substrate which was later bonded to a glass plate using an oxygen plasma cleaner device. Fluidic flow testing was conducted by pumping dye-mixed deionized (DI) water through the channels using a syringe pump and connecting tubes at a constant flow rate of 5ml min−1. The outcomes of this study provide an alternative solution for a simple and low-cost method for microdevice fabrication at a large scale.

Data-driven prediction and optimization of axial compressive strength for FRP-reinforced CFST columns using synthetic data augmentation

Fiber-reinforced polymer (FRP) sheets can be used as additional confinement to improve the load-bearing capacity and durability of concrete-filled steel tubular (CFST) columns. This study presents a data-driven approach aimed at accurately predicting the strength and optimizing the design of FRP-CFST columns under axial compressive loading. To overcome the limited database size (only 287 samples), a synthetic data augmentation technique was developed with recourse to the tabular generative adversarial networks (TGAN). Four machine learning (ML) models were rigorously trained using two distinct schemes “Trained with synthetic - Tested with real” (TSTR) and “Trained with real - Tested with real” (TRTR) to seek out the best strength prediction model. Then the winner model was integrated with the metaheuristic optimization algorithm—nondominated sorting genetic algorithm II (NSGA-II), to optimize both the axial strength and material cost of FRP-CFST columns. This fusion enabled a dual-objective optimization via generating the Pareto front, providing designers with a spectrum of optimal design solutions. It turned out that the categorical gradient boosting model trained with the TSTR mode (CATB-Syn) showed superior performance than the other ML models. Its accuracy also surpassed that of existing design equations. The combination of CATB-Syn with NSGA-II provided a reliable Pareto front, and the interpretability of CATB-Syn was also verified. Thus, the proposed framework opens a new avenue for the efficient design of such double-jacketed columns.

Radiative transfer model and validation for infrared management optical properties of porous polymer materials incorporating impacts of micro-voids

In order to characterize the infrared (IR) radiation absorption and/or emission performances of functional porous polymers which claim to have healthcare functions due to IR excitation and emission by processing technologies, a radiative transfer model was constructed based on the principle of IR radiation, the Beer–Lambert law, the Fresnel’s formula and Planck’s law. The theoretical analysis was conducted for the IR management optical properties of the porous sheet polymer materials, including IR reflection, transmission, absorption and emission behaviours during the dynamic process of IR radiation. A modeling method for characterization and revealing of IR management optical properties and optical and thermal transfer behaviours of the reflection and transmission was then investigated from the structural parameters and the temperature rise characteristics of the porous sheet polymer materials during the dynamic IR radiation process. The model was validated by comparing the predicted values from the radiative transfer model with the measured values from the test results of the validation experiments of eight typical porous sheet polymers in an experimental setup. The model was modified by consideration of the influences of two types of micro-voids defects represented by the porosity of micro structure and the thickness compression ratio. The micro-voids defects factors were added to the structural parameters, and therefore the model was improved and the maximum prediction errors of the transmission and reflection surfaces were mostly less than 10%. The radiative transfer model provides the theoretical fundamentals for the evaluation and guidance of IR management optical performances for new products design, development, fabrication and processing in industrial application of functional porous polymers.

Building Manganese Halide Hybrid Materials with 0D, 1D, and 2D Dimensionalities

In recent years, metal-halide hybrid materials have attracted considerable attention because materials, such as lead-iodide perovskites, can have excellent properties as photovoltaics, light-emitting devices, and photodetectors. These materials can be obtained in different dimensionalities (1D, 2D, and 3D), which directly affects their properties. In this article, we built 0D, 1D, and 2D manganese halide materials with 3-aminopyridine (3AP) or 4-ethylpyridine (4EtP). Two isomorphic complexes with 3AP and manganese chloride ([MnCl2(3AP)4]) or manganese bromide ([MnBr2(3AP)4]) were obtained with the amino group in 3AP assisting in the formation of 0D structures via hydrogen bonding. By modifying the reaction conditions, 3AP can also be used to build a 2D coordination polymer with manganese chloride ([MnCl33AP]− [3APH]+). Unlike 3AP, 4EtP does not provide the opportunity for hydrogen bonding, leading to the formation of two additional isomorphic compounds built of individual 1D chains with manganese chloride ({MnCl3(4EtP)2}n) and manganese bromide ({MnBr2(4EtP)2}n). In the visible region, the 0D and 1D manganese halide compounds have similar photoluminescence properties; however, 0D and 1D have different near-IR emissions. In conclusion, hydrogen-bonding groups can play a role in the formation of discrete manganese-halide units, 1D halide chains, or 2D polymeric sheets.

Effectiveness of lag Bolts, CFRP, and HSS in retrofitting salvaged timber girders

This paper presents the effectiveness of various retrofit techniques in improving the flexural behavior of structural timber. For realistic representation with regard to site application, timber girders are salvaged from a decommissioned highway bridge that has been in service over several decades and are strengthened using lag bolts, carbon fiber reinforced polymer (CFRP) sheets, and hollow steel sections (HSS): the retrofitted girders are referred to as Bolt, CFRP, and HSS, respectively. Each category is repeated three times, and the responses of the 12 unstrengthened and strengthened girders are comparatively evaluated. From a load-carrying capacity point of view, lag bolting is not effective. However, CFRP and HSS result in a capacity increase of up to 156.2% relative to the control girder (Cont). Regarding the load–displacement relationship of these girders, the retrofit systems alter the post-peak behavior of the timber. For instance, the lag bolts that are periodically embedded along the specimens bring about pseudo-yield plateaus. The abrupt failure of the Bolt girder is thus precluded. In addition, the amount of dissipated energy increases in all upgraded girders owing to the presence of the retrofit systems. The failure modes of the individual girders are unique, depending upon the type of retrofit. Except for the HSS girder, the effective elastic moduli of the Cont, CFRP, and HSS girders agree with those measured by a stress wave timer. Parameter estimation theoretically infers the possible range of the experimental findings and ensures the adequacy of the test program.

Terahertz characterization of combined pressure-shear shock loaded aromatic polyurea

Realistic shock loading scenarios imply combined, multiaxial stress states, where the mechanically induced energy competes for failing the material intrinsically due to cohesive failures. Under shock loading, failure encompasses various modes, including spallation, shear bands, microcracking, morphological alteration, phase transformation, and plastic deformation. However, elucidating failure in high strain loading conditions challenges the state-of-the-art characterization due to the disparity interfacing different loading and measurement techniques. This research used a novel spectro-mechanical characterization setup, integrating bulk terahertz spectroscopy synchronized in real-time with mixed-mode laser-induced shock waves. The latter was used to submit polyurea elastomers to concurrent pressure and shear waves by saddling a thin polymer sheet on the hypotenuse of a glass prism. Hence, the laser-induced pressure shock waves underwent simultaneous mode conversion at the glass-polyurea interface at the hypotenuse of the glass prism, effectively submitting the sample to tunable amplitude pressure-shear shock waves. The terahertz spectroscopy, operating in the right-angle reflection configuration, was modified to probe predetermined spots on the polyurea samples at different stress states (adjusted by changing the illumination energy) in a three-step sequence: before, during, and after shock loading. The shock-loaded polyurea samples were also characterized using the optical and scanning electron microscopes, revealing compression-shear and tensile-shear failure modes, including surface depression, nucleation of micro-voids and microcracks, and formation of small planes. The induced stress state based on the illumination energy was quantified using an accompanying finite element simulation, resulting in completing the quasi-isentropic behavior of polyurea elastomers, which was found to be in good agreement with previous experimental data from the plate impact experiments and the predictions based on the Lennard-Jones potential. Time domain analysis of terahertz data, using temporal shifting, hysteresis, and dynamic time warping based on the sum of the Euclidean distances between signal pairs, affirmed the microscopy observations while shedding insights on the elastic and plastic deformations and the reversible conformational changes. Irreversible changes to the macromolecule were also detected using the terahertz data spectral analysis. The current results establish a new experimental framework for fundamentally characterizing polymers and their composites at ultrahigh strain rate loading conditions.

Shear Strengthening of Reinforced Concrete Beams Using Engineered Cementitious Composites and Carbon Fiber-Reinforced Polymer Sheets

This study evaluates the performance of Reinforced Concrete (RC) beams enhanced in shear using Engineered Cementitious Composites (ECCs) and Carbon Fiber-Reinforced Polymers (CFRPs). The experimental study encompasses fifteen RC beams. This set includes one control specimen and fourteen beams fortified in shear with Externally Bonded (EB) composites. Two of these specimens were enhanced with ECC layers, while the remaining were augmented with combined CFRP-ECC layers. Variables in the test included the ECC layer thickness, matrix type, number of CFRP layers, and strengthening configurations such as full wrapping, vertical strips, and inclined strips. The results indicated that the shear capacity of the fortified beams increased by 61.1% to 160.1% compared to the control specimen. The most effective structural performance was observed in the full wrapping method, which utilized a single CFRP layer combined with either 20 mm or 40 mm ECC thickness, outperforming other techniques. However, the inclined strip method demonstrated a notably higher load-bearing capacity than the full wrapping approach for beams with double CFRP layers paired with 20 mm and 40 mm ECC thicknesses. This configuration also exhibited superior ductility compared to the rest. Furthermore, the experimental shear capacities obtained were juxtaposed with theoretical values from prevailing design standards.

The amount of improvement and therapeutic effect of sports health by increasing the viscosity of peach juice through reverse osmosis and polymer membrane

In this study, the performance of polyamide membranes embedded with synthesized silica nanoparticles was evaluated for pomegranate juice concentration using the reverse osmosis (RO) process. The research aims to explore the potential therapeutic benefits and measurable improvements in sports health achieved by employing RO and a polymer membrane to enhance the viscosity of peach juice. The membranes utilized in this study feature a multi-layer structure comprising a non-woven polyester layer for strength, a sulfone polyether polymer sheet, and a polyamide layer synthesized through the copolymerization of m-phenylenediamine and benzene tricarboxylic chloride. To enhance the membrane properties, silica nanoparticles were incorporated into the second layer. The experiment was designed using Design Expert software, considering three parameters: weight percentage of polyether sulfone at three levels (12%, 16%, and 20%), weight percentage of silica nanoparticles at three levels (0%, 0.1%, and 0.2%), and the process pressure at three levels (20, 25, and 30 bar). The optimal membrane configuration obtained from this experimental design consisted of a sulfone polyether polymer content of 16%, silica nanoparticles concentration of 2%, and a working pressure of 23.24 bar. Furthermore, the findings of this study suggest that the application of polymer materials and nanoparticles for membrane modification holds potential benefits for the juice industry in the future. However, it is essential to consider the wide range of factors that can influence the properties of nanocomposite membranes.

Rapid repair of geopolymer concrete members reinforced with polymer composites: Parametric study and analytical modeling

To minimize the carbon production from the cement industry, geopolymers are the suitable replacement cementitious materials in concrete structures. Furthermore, glass fiber-reinforced polymer (GFRP) rebars can play a vital role in replacing the corrosive steel reinforcement in structural components due to their extraordinary performance in humid and aggressive environments. The current research aims to determine the performance efficiency of the rapid repairing process of partially damaged GFRP-reinforced recycled aggregate geopolymer concrete (RGC) compressive members subjected to various types of loading. The behavior of 18 repaired steel- and GFRP-reinforced RGC compressive members was compared using experiments, analytical modeling, and finite element analysis (FEA) in ABAQUS. The rapid repair process was completed using high-strength carbon fiber reinforced polymer (CFRP) sheets. The effectiveness of external CFRP wrapping on the failure modes, strength index, stiffness index, ductility index, peak axial loading capacity, and axial shortening behavior of the repaired members was carefully evaluated. Moreover, FEA and analytical models were proposed to accurately predict the axial behavior of the repaired RGC compressive members. A parametric study is carried out to investigate the effects of various parameters of repaired columns. Both experimental and numerical outcomes discovered that the proposed rapid repair method could considerably recover the peak axial capacity and axial shortening capacity of pre-damaged RGC compressive members.

A Dexamethasone-Loaded Polymeric Electrospun Construct as a Tubular Cardiovascular Implant.

Cardiovascular tissue engineering is providing many solutions to cardiovascular diseases. The complex disease demands necessitating tissue-engineered constructs with enhanced functionality. In this study, we are presenting the production of a dexamethasone (DEX)-loaded electrospun tubular polymeric poly(l-lactide) (PLA) or poly(d,l-lactide-co-glycolide) (PLGA) construct which contains iPSC-CMs (induced pluripotent stem cell cardiomyocytes), HUVSMCs (human umbilical vein smooth muscle cells), and HUVECs (human umbilical vein endothelial cells) embedded in fibrin gel. The electrospun tube diameter was calculated, as well as the DEX release for 50 days for 2 different DEX concentrations. Furthermore, we investigated the influence of the polymer composition and concentration on the function of the fibrin gels by imaging and quantification of CD31, alpha-smooth muscle actin (αSMA), collagen I (col I), sarcomeric alpha actinin (SAA), and Connexin 43 (Cx43). We evaluated the cytotoxicity and cell proliferation of HUVECs and HUVSMCs cultivated in PLA and PLGA polymeric sheets. The immunohistochemistry results showed efficient iPSC-CM marker expression, while the HUVEC toxicity was higher than the respective HUVSMC value. In total, our study emphasizes the combination of fibrin gel and electrospinning in a functionalized construct, which includes three cell types and provides useful insights of the DEX release and cytotoxicity in a tissue engineering perspective.

Convective heat transportation in exponentially stratified Casson fluid flow over an inclined sheet with viscous dissipation

There are numerous applications related to engineering and industrial manufacturing and processing in which the boundary-driven hydromagnetic flow of non-Newtonian fluids play a vital role. Examples includes glass fiber, electronic devices, paper production, medical equipment, filaments, polymer sheets and medicine. Researchers investigated the heat transportation in fluid flows with linear stratification. However, linear stratification fails when there exists large temperature difference between different bodies. Owing to such facts, here our aim is to explore the features of convective heat model in Casson fluid flow with inclined magnetic field with exponential stratification deformed by linearly stretchable inclined sheet. Characteristics of heat transportations are formulated and investigated through viscous dissipation and heat generation. The reduced non-linear governing expressions are solved analytically by homotopic technique. Analysis of velocity and temperature are comprehensively demonstrated through graphs. Further, rate of heat transfer and drag force are computed graphically via various parameters. It is concluded that inclination and magnetic parameters diminish the flow velocity gradually. Further, temperature field intensifies when Biot number is enlarged while it decays with increasing thermal stratification. It is hoped that the present study will help us to form the homogeneous mixtures of fluids at industrial and biomedical levels especially in food liquids, medical syrups, and medicines.

Synthesizing and exploring the structural and optical properties of PVA/PVP/PEG polymeric sheet upon doping with nano nickel oxide (NiO) for CUT-OFF filters

Developing novel composite polymeric materials with noteworthy characteristics is vital for crucial research and optical applications in numerous sectors. Using the solution casting method, the blend of the hydrophilic (polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), and polyethylene glycol (PEG)), polymeric composites was evaluated as host carriers for important metal oxide particles of NiO at different concentrations (0.05,0.27,0.55,2.7,5.5,11.04 wt%). The semi-crystalline structural behavior of the produced polymeric sheets was determined by X-ray diffraction (XRD), the surface morphology and the mean grain size of the NiO nanoparticles were investigated through the scanning electron microscopy (SEM), as well as the presence of the O–H group on the PVA/PVP/PEG polymers was identified by the remarkable Fourier transform-infrared (FT-IR) analysis. Using a UV–Vis spectrophotometer, the remarkable impacts of various NiO dopant ratios on the optical properties, transmittance, absorbance, absorption coefficient, and extinction coefficient, of the considered NiO: PVA/PVP/PEG composite sheets were examined. Pure PVA/PVP/PEG polymeric composites have transmittance spectra that are 91 % in the visible range, then drop to 0 % as raising the concentrations of NiO NPs. Additionally, the π-π transition of blend segments is revealed by the studied NiO-doped PVA/PVP/PEGsheets' absorption spectra, which peak at 350 nm. The direct/indirect bandgaps for the pure polymer are (5.40 and 4.98 eV), and they are reduced to (4.81 and 2.84 eV) with the weight of NiO increased, respectively. Based on the optical energy bandgaps (Eg) of the NiO: PVA/PVP/PEG thin composite sheets, seven different models were used to precisely quantify the nonlinear optical characteristics and linear refractive index (n). With the highest concentrations of NiO, the high-frequency dielectric values increased, and the static dielectric constant decreased. The prepared nanocomposites reduced the intensity of three different types of lasers at a wavelength (635 nm, 532 nm, and 450 nm) and the intensity of optical lampe at power 1036 W/m2. The outstanding findings strongly suggest that the proposed NiO: PVA/PVP/PEG thin composite sheets be designed for various optoelectronic, optical filters, and laser medical applications.