Tej Singh
57970285600
Publications - 26
Optimal design of agro-residue filled poly(lactic acid) biocomposites using an integrated CRITIC-CoCoSo multi-criteria decision-making approach
Publication Name: Scientific Reports
Publication Date: 2025-12-01
Volume: 15
Issue: 1
Page Range: Unknown
Description:
In recent years, there has been a rise in environmental awareness, leading to increased efforts to develop eco-friendly materials as alternatives to petroleum-based polymers. This study examined the performance optimization of poly(lactic acid) (PLA) biocomposites filled with agricultural byproducts at concentrations ranging from 0 to 20% by weight, highlighting their potential as substitutes for commodity plastics. The agro-residues used as fillers were flax seed meal and rapeseed straw. A hybrid decision-making algorithm was proposed, utilizing the “criteria importance through inter-criteria correlation” (CRITIC) alongside the “combined compromise solution” (CoCoSo), aimed at identifying the optimal alternative among the evaluated samples. The algorithm considered several attributes, including mechanical traits evaluated via tensile, flexural, and impact tests, hardness, water absorption, biodegradation, and production cost. The findings revealed that the strength properties, including tensile, flexural, impact, and water absorption, were most advantageous for neat PLA. In contrast, the highest modulus values were recorded for the biocomposite filled with 20 wt% rapeseed straw. The biocomposites exhibit increased hardness as agro-waste content rose, with the highest hardness observed in the biocomposite filled with 20 wt% flax seed meal. The study on biodegradation indicates that a higher content of agro-waste promotes disintegration, with flax seed meal emerging as the most effective additive in this context. The findings show that adding various agricultural byproducts in varying amounts affects the evaluated properties differently. Hence, the hybrid CRITIC-CoCoSo optimization approach is utilized to choose the optimal biocomposite. The findings show that the biocomposite with 20 wt% rapeseed straw demonstrated optimal physico-mechanical and biodegradation properties, making it a promising eco-friendly alternative for future applications.
Open Access: Yes
Comparative analysis of daily global solar radiation prediction using deep learning models inputted with stochastic variables
Publication Name: Scientific Reports
Publication Date: 2025-12-01
Volume: 15
Issue: 1
Page Range: Unknown
Description:
Photovoltaic power plant outputs depend on the daily global solar radiation (DGSR). The main issue with DGSR data is its lack of precision. The potential unavailability of DGSR data for several sites can be attributed to the high cost of measuring instruments and the intermittent nature of time series data due to equipment malfunctions. Therefore, DGSR prediction research is crucial nowadays to produce photovoltaic power. Different artificial neural network (ANN) models will give different DGSR predictions with varying levels of accuracy, so it is essential to compare the different ANN model inputs with various sets of meteorological stochastic variables. In this study, radial basis function neural network (RBFNN), long short-term memory neural network (LSTMNN), modular neural network (MNN), and transformer model (TM) are developed to investigate the performances of these algorithms for the DGSR prediction using different combinations of meteorological stochastic variables. These models employ five stochastic variables: wind speed, relative humidity, minimum, maximum, and average temperatures. The mean absolute relative error for the transformer model with input variables as average, maximum, and minimum temperatures is 1.98. ANN models outperform traditional models in predictive accuracy.
Open Access: Yes
A hybrid CRITIC-MAIRCA framework for optimal phase change material selection in solar distillation systems
Publication Name: International Journal of Thermofluids
Publication Date: 2025-05-01
Volume: 27
Issue: Unknown
Page Range: Unknown
Description:
Phase change materials (PCMs) serve as an efficient thermal energy storage mediums across a range of thermal systems, including solar distillations. The selection of an appropriate PCM candidate is a vital integration aspect that affects solar distillation performance. Therefore, the present research introduces a multi-criteria decision-making (MCDM) framework for identifying suitable PCM candidates for application in solar distillation systems. Evaluation indices include eighteen PCM alternatives and seven criteria, which were established from the literature. Criteria importance through intercriteria correlation (CRITIC) method was used to assign objective weights to the criteria, followed by the MAIRCA (multi-attributive ideal-real comparative analysis) approach to rank PCM alternatives. The proposed MCDM model suggests the suitability of paraffin wax followed by soy wax and beeswax PCMs for solar distillation applications, respectively. The comparative analysis, sensitivity analysis, and Kendall rank correlation effectively validated the rankings, demonstrating a robust positive correlation among the results. This study can serve as a preliminary step for experimental and simulation-based investigations aimed at optimizing the selection of PCM in the early stage, thereby reducing the time and costs associated with further analysis.
Open Access: Yes
Analysis of wind power generation potential and wind turbine installation economics: A correlation-based approach
Publication Name: Results in Engineering
Publication Date: 2025-03-01
Volume: 25
Issue: Unknown
Page Range: Unknown
Description:
Wind energy production is rapidly expanding worldwide, yet studies on wind energy potential in India remain limited. This study evaluates the wind power potential and conducts an economic cost analysis of wind turbine generator installations at varying hub heights (10m to 150 m) across 21 locations in India, representing a novel contribution to the field. The selected locations include 11 sites in Gujarat (Location-1), 10 sites in Tamil Nadu (Location-2), and one site in Ravangla, Sikkim (Location-3). Cubic factors methods are implemented to estimate Weibull parameters. Results reveal that at 150 m hub height, wind power density ranges from 123.17 to 308.86 W/m² in Gujarat, 80.64 to 427.12 W/m² in Tamil Nadu, and 183.24 W/m² in Sikkim. Kaluneerkulam in Tamil Nadu demonstrates excellent wind category potential, with energy costs ranging from $0.0165 to $0.0076 per kWh, decreasing as hub height increases. Sites across all three locations exhibit moderate to steady wind speeds, making them suitable for wind energy exploitation. An economic analysis of nine wind turbine types shows that Tamil Nadu achieves the lowest energy cost variation, followed by Gujarat and Sikkim. This study provides valuable insights for optimizing wind energy utilization in India.
Open Access: Yes
Performance analysis and modelling of circular jets aeration in an open channel using soft computing techniques
Publication Name: Scientific Reports
Publication Date: 2024-12-01
Volume: 14
Issue: 1
Page Range: Unknown
Description:
Dissolved oxygen (DO) is an important parameter in assessing water quality. The reduction in DO concentration is the result of eutrophication, which degrades the quality of water. Aeration is the best way to enhance the DO concentration. In the current study, the aeration efficiency (E20 ) of various numbers of circular jets in an open channel was experimentally investigated for different channel angle of inclination (θ), discharge (Q), number of jets (Jn ), Froude number (Fr), and hydraulic radius of each jet (HRJn ). The statistical results show that jets from 8 to 64 significantly provide aeration in the open channel. The aeration efficiency and input parameters are modelled into a linear relationship. Additionally, utilizing WEKA software, three soft computing models for predicting aeration efficiency were created with Artificial Neural Network (ANN), M5P, and Random Forest (RF). Performance evaluation results and box plot have shown that ANN is the outperforming model with correlation coefficient (CC) = 0.9823, mean absolute error (MAE) = 0.0098, and root mean square error (RMSE) = 0.0123 during the testing stage. In order to assess the influence of different input factors on the E20 of jets, a sensitivity analysis was conducted using the most effective model, i.e., ANN. The sensitivity analysis results indicate that the angle of inclination is the most influential input variable in predicting E20 , followed by discharge and the number of jets.
Open Access: Yes
An Integrative Framework for Healthcare Recommendation Systems: Leveraging the Linear Discriminant Wolf–Convolutional Neural Network (LDW-CNN) Model
Publication Name: Diagnostics
Publication Date: 2024-11-01
Volume: 14
Issue: 22
Page Range: Unknown
Description:
In the evolving healthcare landscape, recommender systems have gained significant importance due to their role in predicting and anticipating a wide range of health-related data for both patients and healthcare professionals. These systems are crucial for delivering precise information while adhering to high standards of quality, reliability, and authentication. Objectives: The primary objective of this research is to address the challenge of class imbalance in healthcare recommendation systems. This is achieved by improving the prediction and diagnostic capabilities of these systems through a novel approach that integrates linear discriminant wolf (LDW) with convolutional neural networks (CNNs), forming the LDW-CNN model. Methods: The LDW-CNN model incorporates the grey wolf optimizer with linear discriminant analysis to enhance prediction accuracy. The model’s performance is evaluated using multi-disease datasets, covering heart, liver, and kidney diseases. Established error metrics are used to compare the effectiveness of the LDW-CNN model against conventional methods, such as CNNs and multi-level support vector machines (MSVMs). Results: The proposed LDW-CNN system demonstrates remarkable accuracy, achieving a rate of 98.1%, which surpasses existing deep learning approaches. In addition, the model improves specificity to 99.18% and sensitivity to 99.008%, outperforming traditional CNN and MSVM techniques in terms of predictive performance. Conclusions: The LDW-CNN model emerges as a robust solution for multidisciplinary disease prediction and recommendation, offering superior performance in healthcare recommender systems. Its high accuracy, alongside its improved specificity and sensitivity, positions it as a valuable tool for enhancing prediction and diagnosis across multiple disease domains.
Open Access: Yes
Selection of straw waste reinforced sustainable polymer composite using a multi-criteria decision-making approach
Publication Name: Biomass Conversion and Biorefinery
Publication Date: 2024-09-01
Volume: 14
Issue: 17
Page Range: 21007-21017
Description:
The valorization of straw waste as a sustainable and eco-friendly resource in polymer composites is critical for resource recycling and environmental preservation. Therefore, many research works are being carried out regarding the development of wheat straw-based polymer composites to identify the reinforcing potential of these sustainable resources. In this study, three different sizes of wheat straw fibers (60–120 mesh, 35–60 mesh, and 18–35 mesh) were used, and their different ratios (0, 2.5, 5, 10, and 20% by weight) were systematically investigated for the physical and mechanical properties of polypropylene-based sustainable composites. The results indicated that the evaluated composites’ properties are strongly dependent on the quantity and size of the utilized wheat straw. Therefore, a preference selection index was applied to rank the developed sustainable polymer composites to select the best composition. Various properties of the composite materials were considered as criteria for ranking the alternatives, namely tensile strength and modulus, flexural stress at conventional deflection and flexural modulus, impact strength, density, water absorption, material cost, and carbon footprint. The decision-making analysis suggests the alternative with wheat straw content of 20 wt.% (35–60 mesh size) dominating the performance by maximizing the beneficial criteria and minimizing the non-beneficial criteria, making it the most suitable alternative. This study will significantly help formulation designers to deal with the amount and size issues when developing polymeric composites.
Open Access: Yes
Agricultural by-product filled poly(lactic acid) biocomposites with enhanced biodegradability: The effect of flax seed meal and rapeseed straw
Publication Name: Composites Part C Open Access
Publication Date: 2024-07-01
Volume: 14
Issue: Unknown
Page Range: Unknown
Description:
The purpose of this research was to develop “green” materials by combining poly(lactic acid) (PLA) with two agricultural by-products, namely flax seed meal (FSM) and rapeseed straw (RSS). The natural fillers (0–20 wt.%) were mixed with PLA through extrusion and then injection molded into specimens. The samples were analyzed for their thermal, morphological, mechanical, and physical features and biodegradability. Thermal properties and crystallinity were analyzed using Differential Scanning Calorimetry (DSC), while the morphology was investigated by Scanning Electron Microscopy (SEM). Mechanical properties were characterized through tensile, flexural, and impact measurements, while surface hardness was evaluated by Shore D tests. Water absorption and biodegradability of the samples were also examined. DSC measurements revealed a nucleating effect of both bio-fillers. Based on the tensile tests, major improvement in stiffness was found with the biocomposites having up to ∼16 % higher Young's modulus than neat PLA (2.5 GPa). It came, however, at the cost of tensile strength, which decreased from 56 to 51 MPa even in the presence of the lowest amount (2.5 wt.%) of FSM. Loss in strength was due to the limited adhesion between the components, as also supported by SEM images. The hardness slightly (1–2 %) improved in the presence of even 2.5 wt.% bio-filler and it remained at that level at higher filler loading as well. Laboratory-scale composting revealed that both fillers facilitated biodegradation with FSM being superior. In the presence of 10–20 wt.% FSM, the rate of decomposition was found to be twice as fast compared to neat PLA.
Open Access: Yes
Silt erosion and cavitation impact on hydraulic turbines performance: An in-depth analysis and preventative strategies
Publication Name: Heliyon
Publication Date: 2024-04-30
Volume: 10
Issue: 8
Page Range: Unknown
Description:
The primary issues in the Himalayan Rivers are sediment and cavitation degradation of the hydroelectric power turbine components. During the monsoon season, heavy material is transported by streams in hilly areas like the Himalayas through regular rainfalls, glacial and sub-glacial hydrological activity, and other factors. The severe erosion of hydraulic turbines caused by silt abrasion in these areas requires hydropower facilities to be regularly shut down for maintenance, affecting the plant's overall efficiency. This article provides an in-depth examination of the challenges that can lead to cavitation, silt erosion, and a decrease in the efficiency of various hydroelectric turbines, and it demands attention on the design, manufacture, operation, and maintenance of the turbines. This study's main objective is to critically evaluate earlier theoretical, experimental, and numerical evaluation-based studies (on cavitation and silt erosion) that are provided and addressed throughout the study. As a part of this study, various strategies for mitigating the effects of these problems and elongating the time that turbine may be utilized before they must be replaced have been provided.
Open Access: Yes
Thermal, thermomechanical and structural properties of recycled polyethylene terephthalate (rPET)/waste marble dust composites
Publication Name: Heliyon
Publication Date: 2024-02-15
Volume: 10
Issue: 3
Page Range: Unknown
Description:
The main objective of this work is to review the capability of using waste marble dust (MD) particles as reinforcing materials in recycled polymeric composites to achieve environmentally friendly materials. In the present study, polymer composites were fabricated from recycled polyethylene terephthalate (rPET) and MD and then analyzed for their structural and thermal properties. Preparation of rPET-based composites containing 0–20 wt% MD was carried out through extrusion and injection molding. For their characterization Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA) were applied. The DSC analysis revealed a nucleating effect of MD on rPET, which was manifested in a higher crystallization temperature (196.7 °C ⇒ 204.4 °C); however, the marble particles were also found to hamper chain mobility, thereby decreasing the crystallinity ratio (23.7 % ⇒ 19.2 %) of rPET and altering its crystalline structure. According to the TGA measurements, a slight increase occurred in the thermal stability of rPET, its major decomposition temperature increased from 446 °C to 451 °C when 20 wt% MD was incorporated into it. DMA showed an improved stiffness in the entire investigated temperature range for MD-filled composites versus neat rPET. Additionally, several factors were derived from the DMA data, including the effectiveness factor, degree of entanglement, and reinforcing efficiency factor which all suggested a decent interaction between the components indicating a proper reinforcing ability of marble powder. However, above 5 wt% MD content the reinforcing efficiency deteriorated due to the agglomeration of filler particles, which was also supported by scanning electron microscopic images.
Open Access: Yes
Comparison of Mechanical Properties of PLA-Based Biocomposites Filled with Different Agricultural By-Products
Publication Name: Advances in Transdisciplinary Engineering
Publication Date: 2024-01-01
Volume: 59
Issue: Unknown
Page Range: 486-493
Description:
In this study, biopolymer composites were developed using poly(lactic acid) (PLA) as a polymer matrix. Various agricultural by-products, including flax seed meal, rapeseed straw, and mustard seed meal, were added as a reinforcement. The research aimed to provide insight into the valorization of cheap, readily available residues generated in the agricultural industry and assess the mechanical properties of composites prepared using them. The experimental fabrication was conducted by compounding PLA with agro-waste particles in 10 and 20 wt% concentrations. These components were melt mixed with a twin-screw extruder and injection molded into standardized forms. The resulting fabricated composites were tested for tensile and flexural mechanical properties and hardness. Through scanning electron microscopy, images of the natural particles were taken to better understand their structure, geometry, and possible ways of interaction between them and the PLA matrix. The results of quasi-static mechanical tests suggest that using agricultural by-products can effectively improve Young's modulus and flexural modulus of PLA but at the cost of tensile and flexural strength, which decreased with the by-products' introduction. Of the three agro-waste options, rapeseed straw emerged as the superior choice because it only marginally reduced the mechanical strength of the PLA and enhanced its stiffness the most. Hardness was the least affected property, test results showed that the added fillers did not substantially change the polymer matrix's hardness.
Open Access: Yes
DOI: 10.3233/ATDE240584
Effect of Maleated Compatibilizer on the Mechanical Properties of PLA/Mustard Waste Biocomposites
Publication Name: Chemical Engineering Transactions
Publication Date: 2024-01-01
Volume: 114
Issue: Unknown
Page Range: 775-780
Description:
Natural fiber polymer composites of biodegradable poly(lactic acid) (PLA) and mustard waste were fabricated with the addition of various amounts (0.25-2.00 wt.%) of maleic anhydride grafted PLA (PLA-g-MA), which was used as a coupling agent to improve interfacial adhesion between the components and thereby enhance the mechanical features of the biocomposite. PLA-g-MA was synthesized in-house by reactive melt grafting using dicumyl peroxide as a free grafting initiator. Preparation of the biocomposite samples was carried out using a twin screw extruder and an injection molding machine. The effect of PLA-g-MA concentration on the samples’ mechanical traits and surface hardness was investigated. Mechanical properties were determined using uniaxial tensile tests, flexural tests, and Charpy impact tests; additionally, the surface hardness was tested with a Shore D indenter. The tensile tests revealed that even the lowest amount (0.25 wt.%) of PLA-g-MA was sufficient to effectively improve the interfacial adhesion between PLA and mustard waste, as manifested in an increased tensile strength (34 to 39 MPa). Similarly, the flexural and the Charpy impact strength also exceeded that of neat PLA/mustard waste biocomposite by 31 % and 45 %, respectively. The addition of compatibilizer in higher concentrations than 0.25 wt.% did not improve the mechanical properties further, ascribed to the excess PLA-g-MA plasticizing the composite. Based on Shore D testing, the compatibilization did not affect the surface hardness of the biocomposites significantly.
Open Access: Yes
DOI: 10.3303/CET24114130
Thermally conductive and electrically resistive acrylonitrile butadiene styrene (ABS)/boron nitride composites: Optimal design using a multi-criteria decision-making approach
Publication Name: Journal of Materials Research and Technology
Publication Date: 2023-09-01
Volume: 26
Issue: Unknown
Page Range: 8776-8788
Description:
The purpose of this work is to propose a decision-making algorithm to select the optimal composite material for thermally conductive but electrically insulating applications, such as microelectronic packaging heat sinks, diodes, and other electronic devices. In particular, an algorithm based on the criteria importance through inter-criteria correlation (CRITIC) and additive ratio assessment (ARAS) methods are used to evaluate several conflicting attributes. The evaluated samples were acrylonitrile butadiene styrene (ABS) composites filled with 0–30 vol% of boron nitride (BN) particles and prepared through melt compounding. The performance attributes considered through testing were heat conductivity, electrical resistivity, density, hardness, and tensile properties (Young's modulus, tensile strength, and elongation). As expected, the composite containing 30 vol% BN exhibited the highest heat conductivity, electrical resistivity, and Young's modulus. Meanwhile, unfilled ABS had the highest elongation at break, tensile strength, and lowest density. With respect to hardness, the 1 vol% BN-loaded composite proved to be superior. Therefore, the experimental data revealed a considerable compositional dependence with no obvious trend. The optimal composition was identified by adopting the CRITIC-ARAS multi-criteria decision-making algorithm, based on which the 30 vol% BN-containing composite was dominant among all the prepared samples. A validation through other decision-making techniques was performed to support the robustness of the proposed technique. Additionally, a sensitivity analysis was carried out on several weight exchange scenarios to see the stability of the ranking results.
Open Access: Yes
Waste marble dust-filled sustainable polymer composite selection using a multi-criteria decision-making technique
Publication Name: Arabian Journal of Chemistry
Publication Date: 2023-06-01
Volume: 16
Issue: 6
Page Range: Unknown
Description:
This research works with the optimal design of marble dust-filled polymer composites using a multi-criteria decision-making (MCDM) technique. Polylactic acid (PLA) and recycled polyethylene terephthalate (rPET)-based composites containing 0, 5, 10, and 20 wt% of marble dust were developed and evaluated for various physicomechanical and wear properties. The results showed that the incorporation of marble dust improved the modulus and hardness of both PLA and rPET. Moreover, a marginal improvement in flexural strength was noted while the tensile and impact strength of the matrices were deteriorating due to marble dust addition. The outcomes of wear analysis demonstrated an improvement in wear resistance up until 10 wt% filler reinforcement, after which the incidence of dust particles peeling off from the matrix was observed, thereby reducing its efficiency. The best tensile modulus of 3.23 GPa, flexural modulus of 4.39 GPa, and hardness of 83.95 Shore D were obtained for 20 wt% marble dust-filled PLA composites. The lowest density of 1.24 g/cc and the highest tensile strength of 57.94 MPa were recorded for neat PLA, while the highest impact strength of 30.94 kJ/m2 was recorded for neat rPET. The lowest wear of 0.01 g was obtained for the rPET containing 5 wt% marble dust content. The experimental results revealed that for the examined criteria, the order of composite preference is not the same. Therefore, the optimal composite was identified by adopting a preference selection index-based MCDM technique. The findings demonstrated that the 10 wt% marble dust-filled PLA composite appears to be the best solution with favorable physical, mechanical, and wear properties.
Open Access: Yes
Performance Optimization of Lignocellulosic Fiber-Reinforced Brake Friction Composite Materials Using an Integrated CRITIC-CODAS-Based Decision-Making Approach
Publication Name: Sustainability Switzerland
Publication Date: 2023-06-01
Volume: 15
Issue: 11
Page Range: Unknown
Description:
A hybrid multicriteria decision-making (MCDM) framework, namely “criteria importance through inter-criteria correlation-combinative distance-based assessment” (CRITIC-CODAS) is introduced to rank automotive brake friction composite materials based on their physical and tribological properties. The ranking analysis was performed on ten brake friction composite material alternatives that contained varying proportions (5% and 10% by weight) of hemp, ramie, pineapple, banana, and Kevlar fibers. The properties of alternatives such as density, porosity, compressibility, friction coefficient, fade-recovery performance, friction fluctuation, cost, and carbon footprint were used as selection criteria. An increase in natural fiber content resulted in a decrease in density, along with an increase in porosity and compressibility. The composite with 5 wt.% Kevlar fiber showed the highest coefficient of friction, while the 5 wt.% ramie fiber-based composites exhibited the lowest levels of fade and friction fluctuations. The wear performance was highest in the composite containing 10 wt.% Kevlar fiber, while the composite with 10 wt.% ramie fiber exhibited the highest recovery. The results indicate that including different fibers in varying amounts can affect the evaluated performance criteria. A hybrid CRITIC-CODAS decision-making technique was used to select the optimal brake friction composite. The findings of this approach revealed that adding 10 wt.% banana fiber to the brake friction composite can give the optimal combination of evaluated properties. A sensitivity analysis was performed on several weight exchange scenarios to see the stability of the ranking results. Using Spearman’s correlation with the ranking outcomes from other MCDM techniques, the suggested decision-making framework was further verified, demonstrating its effectiveness and stability.
Open Access: Yes
DOI: 10.3390/su15118880
Valorization of Waste Wood Flour and Rice Husk in Poly(Lactic Acid)-Based Hybrid Biocomposites
Publication Name: Journal of Polymers and the Environment
Publication Date: 2023-02-01
Volume: 31
Issue: 2
Page Range: 541-551
Description:
This study explores the possibility of developing a new class of hybrid particulate-filled biocomposites using wood flour and rice husk wastes as environmentally friendly additives to poly(lactic acid) (PLA) as matrix material. Samples were prepared with fillers of different concentrations (0, 2.5, 5, 7.5 and 10 wt %), while the ratio of wood flour and rice husk was fixed at 1:1 in all cases. The preparation of biocomposites was performed through extrusion using a twin-screw extruder. Subsequently, they were formed into specimens by injection molding. Mechanical, thermal, thermomechanical, and morphological properties were examined. The addition of natural waste particles resulted in a remarkable improvement both in tensile and flexural modulus; however at a cost of impact strength and tensile strength. Meanwhile, flexural stress at conventional strain values were barely affected by the presence of wood flour and rice husk. The SEM images confirmed that there is a limited interfacial adhesion between the components, which supports the results obtained during mechanical tests. Both the differential scanning calorimetry (DSC) and the dynamic mechanical analysis indicated that the glass transition temperature of PLA was not affected by the incorporation of filler particles; however, the crystalline structure was gradually altered with increasing filler loading according to the DSC. Additionally, the particles were observed acting as nucleating agents, thereby increasing the overall crystallinity of PLA.
Open Access: Yes
Fabrication of Europium-Doped Barium Titanate/Polystyrene Polymer Nanocomposites Using Ultrasonication-Assisted Method: Structural and Optical Properties
Publication Name: Polymers
Publication Date: 2022-11-01
Volume: 14
Issue: 21
Page Range: Unknown
Description:
In the current work, europium-doped barium titanate particles were used as filler material and polystyrene was used as a matrix to fabricate Ba1−3x /2Eux TiO3 /PS polymer nanocomposites with x = 0, 0.005, 0.015 and 0.025. A solid-state reaction was used to synthesize filler particles and the solvent evaporation method was used to form polymer nanocomposites. The effects of ultrasonic treatment were also studied in the formation of nanocomposite materials. The quantitative and qualitative studies were conducted using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), and ultraviolet-visible (UV-Vis) characterization techniques. The XRD data and FTIR data confirm the incorporation of filler particles in the polymer matrix. FE-SEM data confirms that the particles are in the nanophase. The optical band gap was directly affected by the filler particles and it started to reduce as Eu concentration started to increase.
Open Access: Yes
Optimization on physicomechanical and wear properties of wood waste filled poly(lactic acid) biocomposites using integrated entropy-simple additive weighting approach
Publication Name: South African Journal of Chemical Engineering
Publication Date: 2022-07-01
Volume: 41
Issue: Unknown
Page Range: 193-202
Description:
The present research work develops an evaluation method based on the hybrid entropy-simple additive weighting approach to select the best biocomposite material based on several potentially conflicting criteria. Poly(lactic acid) (PLA) biocomposites with varying proportions of wood waste (0, 2.5, 5, 7.5, and 10 by weight) was developed and evaluated for physical, mechanical, and sliding wear properties. The biocomposite containing 10 wt.% wood waste exhibited the lowest density (1.183 g/cm3) and highest modulus properties (tensile modulus = 2.97 GPa; compressive modulus = 3.46 GPa; and flexural modulus = 4.03 GPa). The bare PLA exhibited the highest strength properties (tensile strength = 57.96 MPa; compressive strength = 105.67 MPa; impact strength = 15.25 kJ/m2), whereas flexural strength (100.43 MPa) was the highest for 5 wt.% wood waste filled biocomposite. The wear of PLA decreased with 2.5 wt.% wood waste incorporated and increased with further addition of wood waste. The experimental results revealed a high compositional dependence with no discernible trend. As a result, prioritizing biocomposites' performance to choose the best from various biocomposite alternatives becomes tough. Therefore, a multi-criteria decision-making process based on a hybrid entropy-simple additive weighting approach was applied to find the optimal biocomposite by taking the experimental results as the selection criterion. The results show that the 2.5 wt.% wood waste added PLA biocomposite proved to be the best solution with optimal physical, mechanical, and wear properties. The validation with other decision-making models supports the robustness of the proposed approach in that the 2.5 wt.% wood waste added PLA biocomposite is the most dominating. This study contributes by providing preferences for the selection criteria and assessing the best alternative from the available PLA biocomposites.
Open Access: Yes
Optimal Design of Wood/Rice Husk-waste-Filled PLA Biocomposites Using Integrated CRITIC–MABAC-Based Decision-Making Algorithm
Publication Name: Polymers
Publication Date: 2022-07-01
Volume: 14
Issue: 13
Page Range: Unknown
Description:
Based on the criteria importance through inter-criteria correlation (CRITIC) and the multi-attributive border approximation area comparison (MABAC), a decision-making algorithm was developed to select the optimal biocomposite material according to several conflicting attributes. Poly(lactic acid) (PLA)-based binary biocomposites containing wood waste and ternary biocompos-ites containing wood waste/rice husk with an overall additive content of 0, 2.5, 5, 7.5 and 10 wt.% were manufactured and evaluated for physicomechanical and wear properties. For the algorithm, the following performance attributes were considered through testing: the evaluated physical (density, water absorption), mechanical (tensile, flexural, compressive and impact) and sliding wear proper-ties. The water absorption and strength properties were found to be the highest for unfilled PLA, while modulus performance remained the highest for 10 wt.% rice husk/wood-waste-added PLA biocomposites. The density of PLA biocomposites increased as rice husk increased, while it decreased as wood waste increased. The lowest and highest density values were recorded for 10 wt.% wood waste and rice husk/wood-waste-containing PLA biocomposites, respectively. The lowest wear was exhibited by the 5 wt.% rice husk/wood-waste-loaded PLA biocomposite. The experimental results were composition dependent and devoid of any discernible trend. Consequently, prioritizing the performance of PLA biocomposites to choose the best one among a collection of alternatives became challenging. Therefore, a decision-making algorithm, called CRITIC–MABAC, was used to select the optimal composition. The importance of attributes was determined by assigning weight using the CRITIC method, while the MABAC method was employed to assess the complete ranking of the biocomposites. The results achieved from the hybrid CRITIC–MABAC approach demonstrated that the 7.5 wt.% wood-waste-added PLA biocomposite exhibited the optimal physicomechanical and wear properties.
Open Access: Yes
Thermal and Sliding Wear Properties of Wood Waste-Filled Poly(Lactic Acid) Biocomposites
Publication Name: Polymers
Publication Date: 2022-06-01
Volume: 14
Issue: 11
Page Range: Unknown
Description:
In our study, the effects of wood waste content (0, 2.5, 5, 7.5, and 10 wt.%) on thermal and dry sliding wear properties of poly(lactic acid) (PLA) biocomposites were investigated. The wear of developed composites was examined under dry contact conditions at different operating parameters, such as sliding velocity (1 m/s, 2 m/s, and 3 m/s) and normal load (10 N, 20 N, and 30 N) at a fixed sliding distance of 2000 m. Thermogravimetric analysis demonstrated that the inclusion of wood waste decreased the thermal stability of PLA biocomposites. The experimental results indicate that wear of biocomposites increased with a rise in load and sliding velocity. There was a 26–38% reduction in wear compared with pure PLA when 2.5 wt.% wood waste was added to composites. The Taguchi method with L25 orthogonal array was used to analyze the sliding wear behavior of the developed biocomposites. The results indicate that the wood waste content with 46.82% contribution emerged as the most crucial parameter affecting the wear of PLA biocomposites. The worn surfaces of the biocomposites were examined by scanning electron microscopy to study possible wear mechanisms and correlate them with the obtained wear results.
Open Access: Yes
Development and characterization of composites produced from recycled polyethylene terephthalate and waste marble dust
Publication Name: Polymer Composites
Publication Date: 2022-06-01
Volume: 43
Issue: 6
Page Range: 3951-3959
Description:
The current paper presents the results of a study on the processing and characterization of waste marble powder-reinforced recycled polyethylene terephthalate (rPET) composites. Samples with up to 20 wt% marble dust (MD) content were produced with twin-screw extrusion followed by injection molding. Subsequently, the morphological and mechanical features and the wear resistance of the developed composites were studied. In terms of mechanical properties, the incorporation of MD steadily improved both the tensile and flexural modulus of rPET, while the strength values showed an optimum at 2.5–5.0 wt%, depending on the mode of loading. Above the optimal MD concentration, the strength values deteriorated, however, even at maximum (20 wt%) marble content they were still similar to that of neat rPET, which proves the potential of utilizing waste MD in this specific polymer as filler material. The surface hardness of the fabricated samples also gradually improved with higher marble content, yet it came at the cost of impact toughness. The analysis of wear performance revealed an increasing resistance against wear up to 5.0 wt% filler loading, above which the dust particles got easily peeled off from the matrix, decreasing its efficiency.
Open Access: Yes
DOI: 10.1002/pc.26669
Optimal Design of Ceramic Based Hip Implant Composites Using Hybrid AHP-MOORA Approach
Publication Name: Materials
Publication Date: 2022-06-01
Volume: 15
Issue: 11
Page Range: Unknown
Description:
Designing excellent hip implant composite material with optimal physical, mechanical and wear properties is challenging. Improper hip implant composite design may result in a premature component and product failure. Therefore, a hybrid decision-making tool was proposed to select the optimal hip implant composite according to several criteria that are probably conflicting. In varying weight proportions, a series of hip implant composite materials containing different ceramics (magnesium oxide, zirconium oxide, chromium oxide, silicon nitride and aluminium oxide) were fabricated and evaluated for wear and physicomechanical properties. The density, void content, hardness, indentation depth, elastic modulus, compressive strength, wear, and fracture toughness values were used to rank the hip implant composites. It was found that the density and void content of the biocomposites remain in the range of 3.920–4.307 g/cm3 and 0.0021–0.0089%, respectively. The composite without zirconium oxide exhibits the lowest density (3.920 g/cm3), while the void content remains lowest for the composite having no chromium oxide content. The highest values of hardness (28.81 GPa), elastic modulus (291 GPa) and fracture toughness (11.97 MPa.m1/2) with the lowest wear (0.0071 mm3/million cycles) were exhibited by the composites having 83 wt.% of aluminium oxide and 10 wt.% of zirconium oxide. The experimental results are compositional dependent and without any visible trend. As a result, selecting the best composites among a group of composite alternatives becomes challenging. Therefore, a hybrid AHP-MOORA based multi-criteria decision-making approach was adopted to choose the best composite alternative. The AHP (analytic hierarchy process) was used to calculate the criteria weight, and MOORA (multiple objective optimisation on the basis of ratio analysis) was used to rank the composites. The outcomes revealed that the hip implant composite with 83 wt.% aluminium oxide, 10 wt.% zirconium oxide, 5 wt.% silicon nitride, 3 wt.% magnesium oxide, and 1.5 wt.% chromium oxide had the best qualities. Finally, sensitivity analysis was conducted to determine the ranking’s robustness and stability concerning the criterion weight.
Open Access: Yes
DOI: 10.3390/ma15113800
Physical, mechanical, and thermal properties of Dalbergia sissoo wood waste-filled poly(lactic acid) composites
Publication Name: Polymer Composites
Publication Date: 2021-09-01
Volume: 42
Issue: 9
Page Range: 4380-4389
Description:
The present work intended to investigate the effect of Dalbergia sissoo wood waste on physical, mechanical, and thermal properties of poly(lactic acid) (PLA)-based composites. The composite specimens, containing wood waste (2.5%, 5%, 7.5%, and 10% by weight) mixed with PLA granules, were prepared by melt compounding. It was found that increased wood waste content resulted in higher modulus, porosity, and water absorption with decreased density, tensile strength, impact strength, and stress at break. Nevertheless, the flexural strength values of the composites were similar to unfilled PLA and they remained almost constant irrespective of the wood waste content. Differential scanning calorimetry analysis revealed that the presence of wood waste content increased the glass transition and cold crystallization temperature of the PLA composites. Moreover, the fractured surfaces of the composites were examined with a scanning electron microscope to study the possible failure mechanisms. The conducted investigations demonstrated that low-cost wood waste-based composites can be used as an environmentally and economically attractive substitute for lightweight applications.
Open Access: Yes
DOI: 10.1002/pc.26155
Utilization of Waste Marble Dust in Poly(Lactic Acid)-Based Biocomposites: Mechanical, Thermal and Wear Properties
Publication Name: Journal of Polymers and the Environment
Publication Date: 2021-09-01
Volume: 29
Issue: 9
Page Range: 2952-2963
Description:
The aim of this present work was to study the applicability of waste marble dust (MD) in poly(lactic acid) (PLA)-based composites. Samples containing up to 20 wt% waste MD were prepared via melt blending. The attention was focused on the investigation of mechanical, morphological, thermal properties and the wear resistance of the PLA/MD composites. Regarding the mechanical properties, both the tensile and the flexural modulus improved remarkably, however, a slight loss was observed in strength and deformability. The impact toughness showed an increasing tendency up to 10 wt% MD loading, which was followed by a marginal decrease at higher concentration. With respect to the sliding wear rate, the composite with the highest MD content showed the best wear resistance. According to the DSC measurements, the MD hampered the chain mobility of PLA, thereby reducing the crystalline ratio. Overall, composites with improved properties were developed, while the reuse of waste MD is expected to reduce the production costs as well.
Open Access: Yes
Antibacterial and anti-inflammatory activities of Cassia fistula fungal broth-capped silver nanoparticles
Publication Name: Materials Technology
Publication Date: 2021-01-01
Volume: 36
Issue: 14
Page Range: 883-893
Description:
The growing need for sustainable technologies has attracted considerable interest in the synthesis of ecofriendly materials. This paper reports the anti-inflammatory and antibacterial activities of sustainable silver nanoparticles (AgNPs) fabricated using endophytic fungus extracted from a medicinal plant, Cassia fistula. Fourier transform-infrared and UV-visible were used for AgNPs characterisation. X-ray diffraction, scanning electron microscope, energy dispersive X-ray analysis, atomic force microscope (AFM), transmission electron microscope and dynamic light scattering analysis revealed that the biosynthesised AgNPs were within the size of ~4–54 nm. The synthesised AgNPs displayed considerable antibacterial activity against Staphylococcus aureus, Escherichia coli and Klebsiella pneumonia bacterial strains. Additionally, synthesised AgNPs showed significant anti-inflammatory potential.
Open Access: Yes
Fabrication of waste bagasse fiber-reinforced epoxy composites: Study of physical, mechanical, and erosion properties
Publication Name: Polymer Composites
Publication Date: 2019-09-01
Volume: 40
Issue: 9
Page Range: 3777-3786
Description:
The aim of the research work is to study the physical, mechanical, and erosive wear properties of sugarcane bagasse fiber-reinforced epoxy composites. The physical (density, void content) and the mechanical (hardness, tensile strength, impact energy, flexural strength) properties of the composites were found to increase with the content of bagasse fiber. For erosive wear analysis, the experiments were carried out with the help of erosion test machine. To minimize the erosive wear rate, Taguchi technique is executed to explore the influence of five control factors including fiber content, impact velocity, impingement, stand-off distance, and erodent size at three levels. Using Taguchi (L27 ) orthogonal array, the optimal combination of control factors, which yielded minimum erosive wear rate, was statistically predicted and experimentally verified. The fiber content and impact velocity were the two most contributing control factors for the minimization of erosive wear rate. The important sequence of the parameters is fiber content > impact velocity > impingement angle > erodent size > stand-off distance. The optimal combination of control factors was obtained at 10 wt% of fiber content, 30 m/s of impact velocity, 30° of impingement angle, 85 mm of stand-off distance, and 250 μm of erodent size. Finally, composites worn surfaces were examined with scanning electron microscope to study the possible erosive wear mechanism. POLYM. COMPOS., 40:3777–3786, 2019. © 2019 Society of Plastics Engineers.
Open Access: Yes
DOI: 10.1002/pc.25239
