Journal of Applied Research of Chemical -Polymer Engineering

Abstract Research Topic:
This review article focuses on recent advancements in enhancing the mechanical, thermal, electrical, and corrosion-resistant properties of epoxy resin through the incorporation of surface-modified zinc oxide nanoparticles. The main objective of this review is to highlight the role of nanoparticle surface modification and weight fraction on the performance of epoxy nanocomposites and to provide a comprehensive overview of the findings reported in previous studies.
Research Method:

In this review, scientific articles and experimental studies on epoxy nanocomposites containing zinc oxide nanoparticles were systematically analyzed. Selected studies were evaluated based on criteria such as the type of nanoparticle surface modification, dispersion and mixing methods, nanoparticle weight fraction, and their effects on the mechanical and thermal properties of the epoxy matrix. Additionally, the findings related to hybrid nanocomposite structures and their synergistic effects were summarized.
Main Findings:

The review indicates that uniform dispersion of nanoparticles in the epoxy matrix improves interfacial adhesion, prevents stress concentration and crack propagation, and consequently enhances the overall strength and durability of the material. Most studies suggest that low nanoparticle loadings (0.25–1 wt%) promote better dispersion and improved mechanical properties, whereas higher loadings may cause particle agglomeration and reduced performance. Surface modification of nanoparticles with silane or amine groups enhances compatibility with the polymer matrix, improves stress transfer, and increases thermal stability. Furthermore, recent studies show that hybrid nanocomposite structures create synergistic effects, simultaneously enhancing multiple performance characteristics. Overall, the incorporation of surface-modified nanoparticles into epoxy resin demonstrates significant potential for developing advanced materials in electronics, photonics, marine, medical, and aerospace applications.

Abstract Research Subject: Synthesis of functionalized magnetic nanosorbent and determination of adsorbent properties, optimization of adsorption laboratory conditions, modeling and optimization of adsorption laboratory conditions, and determination of the kinetics of monoethylene glycol adsorption in wastewater samples by magnetic nanosorbent cobalt ferrite-triaminopropyltriethoxysilane-chitosan
Research Approach: In this research, a functionalized magnetic nanosorbent was used to remove the pollutant monoethylene glycol (MEG) from wastewater. This adsorbent was synthesized by attaching chitosan to the surface of magnetic cobalt ferrite nanoparticles CoFe2O4, and through the intermediate triaminopropyltriethoxysilane (APTES). Chitosan has a high ability to absorb organic pollutants such as monoethylene glycol due to its amino and hydroxyl functional groups. Also, the use of chitosan increases the contact surface and consequently increases the capacity of the adsorbent. The magnetic property of cobalt ferrite leads to easy separation of the adsorbent from the wastewater sample by creating a magnetic field. The properties of the synthesized adsorbent were investigated using Fourier Transform Infrared (FTIR) spectroscopy, Vibrating Sample Magnetometer (VSM), Thermogravimetric Analysis (TGA), and Scanning Electron Microscope (SEM). The optimal adsorption conditions, including pH, adsorbent saturation time, and adsorbent recovery through the adsorption and desorption cycle, were investigated.
Main results: The optimal pH value for glycol adsorption from a wastewater sample by functionalized magnetic nanosorbent was determined to be 6, and the contact time for apparent equilibrium of the adsorbent was determined to be 5 minutes, which indicates the availability of adsorbent sites for glycol. Also, the change in adsorption capacity after 10 stages of adsorption and desorption cycle was less than 21%, which indicates the high recovery capability of the adsorbent and its economic efficiency. Adsorption kinetic data were investigated by three kinetic models: pseudo-first order, pseudo-second order, and Intra-particle diffusion. Considering the higher correlation coefficient in the pseudo-second-order model (R2 = 0.9951), it can be concluded that the adsorption of glycol on the synthesized adsorbent is most consistent with this model.

Abstract Abstract

Research subject:
Bioleaching of lithium has emerged as an innovative and sustainable approach for extracting this valuable metal from solid sources, including mineral ores, spent lithium-ion batteries, and other electronic waste. The increasing global demand for lithium-ion batteries, especially for consumer electronics and electric vehicles, has intensified the need for efficient lithium resource recovery. Given the environmental and economic challenges associated with traditional extraction methods, bioleaching has been proposed as an eco-friendly and cost-effective alternative.


Research approach:

This study provides a comprehensive review of the scientific literature and research on lithium bioleaching. It begins with an overview of lithium resources and applications, followed by an evaluation of studies on the bioleaching of lithium-ion batteries and other solid sources. The mechanisms involved and commonly used microorganisms are analyzed. Additionally, key parameters influencing metal recovery efficiency—such as pH, temperature, medium composition, pulp density, and leaching time—are investigated. The study also explores innovative approaches, including the use of artificial intelligence, systems biology, and synthetic biology, to optimize bioleaching processes.


Main results:

The findings demonstrate that bioleaching not only achieves efficient lithium recovery from solid sources but also significantly reduces environmental hazards. Spent lithium-ion batteries are identified as a rich and valuable source for lithium extraction. The use of microorganisms such as Aspergillus niger and Acidithiobacillus ferrooxidans has achieved lithium recovery rates of up to 100%. Studies indicate that optimizing microbial strains through synthetic and systems biology, along with refining cultivation conditions using modern AI-based techniques, can address industrial challenges in bioleaching. Furthermore, this research highlights the role of bioleaching in promoting a circular economy and presents a promising outlook for its industrial application in sustainable lithium resource recovery.

Abstract Research subject: This study investigates the effect of poly(butyl acrylate) (PBA)-based polymeric plasticizers on the performance of poly(vinyl chloride) (PVC) films. The main objectives were the synthesis and evaluation of graft copolymer plasticizers, PVC-g-PBA, with varying PBA chain lengths, and the examination of their impact on the microstructure, mechanical properties, and stability of PVC films.
Research approach: PBA chains with different molar percentages (40–80%) were grafted onto PVC chains via atom transfer radical polymerization (ATRP). The microstructures of the synthesized copolymers were confirmed using Fourier-transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (¹H-NMR). These copolymers were then used as plasticizers (at 22 wt%) in the preparation of PVC films. The mechanical properties (tensile strength and elongation at break), morphology (via wide-angle X-ray diffraction (WAXD)), plasticizer stability in the PVC matrix (extraction test), and thermomechanical behavior (via dynamic mechanical thermal analysis (DMTA)) were evaluated.
Main results: Increasing the molar percentage of PBA in the copolymers reduced the yield stress from 53 to 10 MPa, while significantly increasing the elongation at break from 9% to 162%, indicating enhanced flexibility of the PVC films. WAXD results revealed that at lower PBA contents (up to 63%), chain ordering improved, whereas higher PBA incorporation (73%) led to a notable reduction in crystallinity due to the amorphous nature of PBA. The extraction test confirmed the high stability of the synthesized plasticizers in the PVC matrix after 24 hours. DMTA analysis indicated shifts in the glass transition temperature between phases as the PBA content increased. Compared to the conventional plasticizer dioctyl phthalate (DOP), the synthesized plasticizers exhibited superior mechanical performance and are proposed as a highly stable alternative for PVC applications.

 

Abstract Research subject: In this study, glucosamine-functionalized core–shell nanoparticles were synthesized. Subsequently, the nanoparticle synthesis was confirmed using various characterization techniques, and the synthesized nanoparticles were applied for heavy metal separation. To this end, Fe₃O₄@SiO₂ magnetic core–shell nanoparticles were synthesized via co-precipitation and Stöber methods. The core–shell nanoparticles were subsequently functionalized with cyanuric chloride and glucosamine. Glucosamine-functionalized nanoparticles were used as effective adsorbents for the removal of cadmium ions from aqueous solutions via solid-phase extraction.

Research approach: Morphological, structural, and magnetic properties, as well as particle size of the nanoparticles during synthesis, were investigated using transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), dynamic light scattering (DLS), and X-ray diffraction (XRD). Additional analyses included Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), energy-dispersive X-ray spectroscopy (EDX), and vibrating sample magnetometry (VSM). Subsequently, the effects of various parameters—including adsorbent dosage, contact time, and solution pH—on adsorption performance were investigated.
Main results: The results indicated that the maximum cadmium adsorption capacity (145 mg/g) was achieved when 15 mg of adsorbent was added to 50 mL of solution with an initial concentration of 0.4 mmol/L over 18 minutes at pH 7. In addition, the synthetic nanoadsorbent was recycled and reused for six consecutive adsorption–desorption cycles using a magnet, without significant loss in adsorption performance. Glucosamine-functionalized core–shell nanoparticles are proposed as a promising technology for water and wastewater treatment, owing to their high adsorption capacity and reusability in sequential adsorption–desorption cycles.

Abstract Today, different filament cross-sectional shapes of spinneret are used in the production of synthetic multifilament yarns to create various applications and properties. This research aimed to investigate the effect of round and rectangular cross-sectional shapes of polyethylene terephthalate (PET) multifilament yarn on the physical and crimp properties of melt-spun and draw-textured yarn with partially oriented yarns (POY) produced by an industrial melt spinning machine and then draw textured yarns (DTY) was produced by an industrial frictional false twist texturizing machine under the same conditions. All yarn samples with two round and rectangular cross-sectional shapes, linear density, thermal shrinkage, degree of crystallinity, and tensile properties (strength, elongation at break, and initial modulus) were analyzed. Also, for DTY yarns, in addition to the mentioned tests, the crimp properties (crimp shrinkage, crimp modulus, and crimp stability), the amount of resiliency, and the ratio of tension after twisting zone to tension before twisting zone (T2/T1) were also investigated. In addition, to know the microstructural condition of fibers, an X-ray diffraction test was performed for textured yarn samples. According to the results, it was found that the difference in tensile properties and thermal shrinkage of POY yarns of both cross-sections is small, despite the statistical significance. However, these variations are greater for two round and rectangular cross-sectional shapes in DTY yarns. In comparing the resiliency values of DTY yarns, the yarn with a rectangular cross-sectional shape showed a higher resiliency value than the round cross-sectional shape. In addition, the crimp properties of DTY yarn with a round cross-sectional shape were better than a rectangular cross-sectional surface, which can be attributed to its higher crystallinity and consequently, softness and texturability compared to a round cross-sectional shape.
 

Abstract Research subject: Oil-based wastewater treatment is essential to prevent environmental harm and comply with regulations. Membrane processes are ideal for this due to their efficiency, low energy use, and ability to handle complex emulsions effectively.
Research approach: The primary goal of this study is to employ an ultrafiltration membrane separation process for the treatment of wastewater containing oil compounds (e.g., diesel fuel). To achieve this, polyethersulfone/sulfonated-polyethersulfone (PES/SPES) blend membranes with various SPES loadings were fabricated using the nonsolvent-induced phase separation (NIPS) method. The effects of SPES loading on the membrane morphology, surface roughness, surface hydrophilicity, mechanical strength, porosity, and water and wastewater flux were investigated using scanning electron microscopy (SEM), atomic force microscopy (AFM), water contact angle measurement, mechanical strength testing, and filtration performance tests, respectively.
Main results: The results showed that adding SPES to PES and increasing the loading of SPES led to the formation of macrovoids in the membrane cross-section, enhanced surface roughness and hydrophilicity, increased porosity, improved water and wastewater flux, and increased the pure water flux recovery ratio. However, these benefits came with reduced mechanical strength and increased membrane compaction. Among the prepared membranes, the PES/SPES (60/40 wt./wt.) blend membrane exhibited the best filtration performance, achieving a final wastewater flux of 34.78 L/m²·h, compared to 11.35 L/m²·h for the neat PES membrane. Meanwhile, the PES/SPES (40/60 wt./wt.) composite demonstrated the highest surface roughness, hydrophilicity, and flux recovery ratio. Notably, all membranes synthesized in this study achieved over 99% rejection efficiency for the diesel fuel-water emulsions, which is significant for practical and industrial applications.

Abstract Research subject: In this study, Fe₃O₄ nanoparticles were synthesized using the co-precipitation method. Subsequently, core–shell Fe₃O₄@SiO₂ nanoparticles were prepared via the Stöber method using tetraethoxysilane as the silica source. In the next step, the core–shell nanoparticles were functionalized with theophylline molecules. Finally, these nanoparticles were employed as an adsorbent for the removal of nickel ions from aqueous solutions using the solid-phase extraction method.

Research approach: The structural, crystalline, thermal, magnetic, morphological, and size-related properties of the nanoparticles were investigated using X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, vibrating sample magnetometry, transmission electron microscopy, and scanning electron microscopy. The key parameters affecting solid-phase extraction were then optimized following confirmation of the successful synthesis of the proposed nanostructure. For this purpose, the effects of adsorbent dosage, contact time, pH, and initial nickel ion concentration on adsorption capacity were systematically studied.

Main results: The results showed that using 27 mg of adsorbent in 75 mL of nickel ion solution with an initial concentration of 0.45 mmol/L achieved a maximum adsorption capacity of 94% at pH 7 within 28 minutes at ambient temperature. Furthermore, the recyclability and reusability of the nanoadsorbent were examined through sequential adsorption–desorption cycles using an external magnet. The results demonstrated excellent performance in removing divalent nickel ions from aqueous solutions. Moreover, the synthetic nanoadsorbent could be recovered and reused across successive adsorption–desorption cycles without any loss of functional activity.

Abstract Research subject: Real-time analysis using digital tools requires receiving instantaneous data from various points in industrial chemical processes. Time delays in measurements of process variables can affect the effective performance of different control strategies, process stability, and operational efficiency, making it impossible to analyze, extract information, and convert it into actionable decisions in real-time. The synthesis process of vinyl acetate monomer is recognized as a benchmark dynamic and nonlinear process in the chemical industry. In this process, the composition of water at the bottom of the azeotropic distillation column is one of the important variables measured by a gas chromatography (GC) analyzer, which has a significant time delay and high cost.

Research approach: Soft sensors primarily improve the real-time estimation of variables that are difficult or impossible to measure. Neural networks play an important role in the development of soft sensors due to their ability to learn nonlinear patterns and their suitable prediction speed. This study focuses on the development of a soft sensor based on a feedforward neural network model for real-time estimation of the composition of water at the bottom of an azeotropic distillation column in the vinyl acetate monomer synthesis process.

Main results: Additionally, the model was adaptively implemented under various fault conditions and accurately estimates the GC analyzer behavior instantaneously, achieving a mean squared error (MSE) of 1.1 × 10-5. Maintaining prediction accuracy in the adaptive implementation of soft sensors in the presence of various process faults demonstrates the effective adaptability of these sensors. Therefore, this study demonstrates the capability of soft sensors as an efficient and cost-effective alternative for real-time monitoring of complex chemical processes.