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CuWO4/Ti3C2 MXene Heterostructure: Fabrication and Immobilization into a Photocatalytic PVDF Membrane

Fibers and polymers 2025年第4期26卷 1493-1505页

作者： Mostafavi Mousavi, Amirali Sabbagh Alvani, Ali Asghar Salimi, Reza Department of Polymer Engineering and Color Technology Amirkabir University of Technology Tehran*** Iran Amirkabir University of Technology Tehran*** Iran

Pollution of water caused by organic contaminants is a significant global environmental concern that has paid increasing attention. polymeric photocatalytic membranes (PPMs) are attracting significant attention for their role in water purification, with benefits of both photocatalysis and membrane separation. In this study, we synthesized a hybrid CuWO4/Ti3C2 MXene heterojunction and immobilized the as-prepared photocatalyst into a polyvinylidene fluoride (PVDF) membrane using phase inversion method to fabricate a photocatalytic membrane system. The CuWO4/Ti3C2 heterostructure, prepared by the hydrothermal method, and immobilized CuWO4/Ti3C2/PVDF membrane exhibit a significant activity in photocatalytic MB degradation performance which is 1.82 and 1.66 times higher than that of pure ones, respectively. This improvement is attributed to the energy band structure of the Schottky heterojunction, leads to enhanced charge transfer efficiency of photo-induced electrons from CuWO4 to Ti3C2 and reduced electron–hole recombination, confirmed by Mott–Schottky and photoluminescence (PL) spectroscopy. Based on the obtained results, the immobilized CuWO4/Ti3C2/PVDF membrane with a satisfactory reusability can be considered as a promising polymeric photocatalytic membrane for water treatment applications. © The Author(s), under exclusive licence to the Korean Fiber Society 2025.

关键词： Reusability

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A pragmatic approach to analyze the ability of ethylene-octene copolymer in the long chain branching of polypropylene in molten and solid state

SPE Polymers

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SPE polymers 2024年第2期5卷 151-168页

作者： Negaresh, Mohammadmahdi Karbalaei-Bagher, Milad Jahani, Yousef Forouzan, Ali Department of Polymer Engineering and Color Technology Amirkabir University of Technology Tehran Iran Plastic Department Faculty of Processing Iran Polymer and Petrochemical Institute Tehran Iran

The investigation of chain branching in polypropylene (PP) holds significant importance for comprehending the impact of structural modifications on the properties of PP. The utilization of ethylene-octene copolymer (EOC) presents a valuable opportunity to examine the influence of branching density on the ability of electron beam irradiation or a chemical agent in a PP blend. The introducing long chain branches (LCB) into PP can enhance its mechanical properties, particularly impact strength. This characteristic is of particular significance in applications where the material is subjected to mechanical stress, such as automotive components or packaging materials. Blends of PP/EOC were produced using 20 and 30 wt% of EOC and 0.5 phr trimethylolpropane trimethacrylate (TMPTMA) monomer. To evaluate the efficiency of branching in both solid and molten states, irradiated samples and samples mixed with dicumyl peroxide (DCP) were selected. The rheological properties of the molten blends in shear and extensional modes were assessed, and their morphology was examined using scanning electron microscopy. The existence of LCB in all samples was confirmed through dynamic viscoelastic measurements. It was concluded that although the irradiation promoted chain scission within the backbone, which resulted in long chain branching, DCP created LCB on the backbone chains of PP through chemical reaction in the melt state. Additionally, the strain hardening constant (n) was calculated, and its value for the irradiated sample PP/EOC 80/20 was 0.19, whereas its value for this blend when employing DCP was 0.14. While the complex viscosity of irradiated blend (8764 Pa.s) was greater than that of melt state branched blend (8377 Pa.s) at 0.1 rad/s, in the higher frequencies it became smaller due to the more effective creation of long chain branches through peroxide grafting in the molten state. The results of the study verified the presence of LCB in the materials by observing longer relaxati

关键词： ethylene-octene copolymer irradiation multifunctional monomer peroxide polypropylene

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Investigating the effect of Al and Mg dopedhydroxyapatite coating on improving the corrosion resistance of Mg substrates for implants application 31

Investigating the effect of Al and Mg dopedhydroxyapatite co...

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31st National and 9th International Iranian Conference on Biomedical engineering, ICBME 2024

作者： Heydarinasab, H. Sadeghi, F. Haj Ramezanzadeh, B. Mohammadloo, H. Eivaz Amirkabir University of Technology Faculty of Polymer Engineering and Color Technology Tehran Iran Institute for Color Science and Technology Surface Coating and Corrosion Department Tehran Iran Iran Polymer and Petrochemical Institute Colour Resin and Surface Coatings Department Tehran Iran

ISBN: (纸本)9798331529710

considering its advantageous properties and resemblance to natural bone, hydroxyapatite (HA) coatings have garnered a lot of interest as a means of enhancing the corrosion resistance of magnesium implants. In this study, the efficacy of HA coatings doped with aluminum (AI-HA) and magnesium (Mg-HA) in enhancing the corrosion protection of magnesium AZ31 substrates for implant applications was investigated. Morphological analysis via Scanning Electron Microscope (SEM) confirmed the hydroxyapatite coating formation with a regular crystalline structure. Fourier Transform Infrared Spectroscopy (FTIR) offered further confirmation of the presence of HA coatings on the magnesium surfaces. Analysis using Electrochemical Impedance Spectroscopy (EIS) revealed that both AI-HA and Mg-HA coatings considerably enhanced the magnesium substrates' resistance to corrosion when compared to the samples without coatings. Remarkably, the Mg-HA coating displayed superior corrosion protection, which can be attributed to its more homogeneous structure, reduced defects, and enhanced coverage, along with a stronger interface with the underlying magnesium substrate, in comparison to the AI-HA coating. With implications for the long-term functionality and therapeutic relevance of such biomedical devices, These results demonstrate the significant promise of magnesium-doped HA coatings as a practical means of improving the corrosion resistance of implants made of magnesium. © 2024 IEEE.

关键词： Fourier transform infrared spectroscopy

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Effects of copper and manganese cations on cerium-based conversion coating on galvanized steel:Corrosion resistance and microstructure characterizations

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Journal of Rare Earths 2022年第6期40卷 1002-1006,I0006页

作者： Farzaneh Khast Mesbah Saybani Ali Asghar Sarabi Dariani Corrosion Engineering and Material Protection Group Bandar Abbas CampusAmirkabir University of TechnologyTehranIran Department of Maritime Engineering Amirkabir University of TechnologyTehranIran Department of Color and Polymer Engineering Amirkabir University of TechnologyTehranIran

The cerium conversion coating(CeCC) containing copper and manganese cations was applied to the galvanized *** microstructure and the composition of specimen were analyzed by field emission scanning electron microscopy(FE-SEM) and energy dispersive spectroscopy(EDS).Electrochemical impedance spectroscopy(EIS) and polarization tests were conducted in 3.5 wt% NaCl solution to investigate the coating corrosion *** results show that there are improvements in corrosion resistance and microstructure of CeCC containing copper and manganese cations but copper ions increase corrosion resistance of CeCC from 5800 to 27000 Ω·cm^(2).

关键词： Conversion coating Galvanized steel EIS Copper Manganese Rare earths

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Advanced mathematical modeling and kinetic analysis of gas-phase propylene polymerization using an orifice controller: Implications for polymer properties

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Chemical engineering Research and Design 2025年 219卷 149-166页

作者： Yazdanbakhsh, Amirhosein Haddadi-Asl, Vahid Rostamipoor, Hadi Abdollahi, Elahe Shahrasari, Asal Narjili, Sajede Department of Polymer Engineering and Color Technology AmirKabir University of Technology P.O. Box Tehran15875-4413 Iran

Gas-phase propylene polymerization using Ziegler-Natta catalysts is a complex process influenced by heat and mass transfer, kinetic parameters, and control strategies. This study presents a comprehensive mathematical model to simulate polymerization behavior, incorporating differential equations for temperature, monomer concentration, and polymerization kinetics. Accordingly, a Proportional-Integral-Derivative (PID) controller is designed and implemented to regulate pressure fluctuations and maintain stable reaction conditions. The numerical model is iteratively solved using the Levenberg-Marquardt method, enhancing the model's predictive accuracy for polymer properties to within 5 %. The results of the PID controller confirm its effectiveness in stabilizing pressure at 6 × 10⁵ Pa within 40 s by mitigating initial oscillations, while reactor medium temperature fluctuations are maintained within ± 0.01 K. This leads to a significant improvement in the polymer's molecular weight distribution, with a polydispersity index (PDI) of approximately 5.3, indicating better product uniformity. Furthermore, by optimizing kinetic parameters, catalyst efficiency is enhanced, increasing polymer yield by 10 % under optimal conditions. This study integrates rigorous modeling with precise control strategies, offering valuable insights into optimizing polymerization processes to improve product quality and enhance process scalability—critical factors for real-world manufacturing applications. © 2025 Institution of Chemical Engineers

关键词： Numerical models

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Polypropylene/ethylene blend–Cloisite nanocomposites: preparation and characterization

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Iranian polymer Journal 2025年 1-11页

作者： Darkoush, Babak Nazockdast, Hossein Ahmadi, Zahed Department of Polymer Engineering and Color Technology Amirkabir University of Technology (Tehran Polytechnic) Tehran Iran Department of Chemistry Amirkabir University of Technology Tehran Iran

A polymer matrix of polyolefin/clay nanocomposites with polypropylene/ethylene–octane copolymer (EOC) blend and Cloisite 15A as a nanofiller was fabricated and characterized. The nanocomposites were prepared with a fixed PP/EOC blend ratio, and different amounts of nanofiller, including 0, 1, 3, and 5% (by wt). The structural, morphological, rheological, and mechanical properties of the nanocomposites were evaluated by various tests. XRD results showed that with increasing the amount of nanofillers, the d-spacing of clay increased, while the size of clay galleries decreased. SEM images revealed that by incorporating nanofillers into the polymer blend, the size of dispersed phase decreased from 152 nm in the polymer blend to 123 nm in the nanocomposite with 5% (by wt) Cloisite. Rheometrics mechanical spectrometer (RMS) results disclosed that the complex viscosity, storage modulus, shear-thinning behavior, and relaxation time increased proportionally with the amount of nanofillers, and the nanocomposite with 5% (by wt) Cloisite had the highest solid-like behavior. Mechanical test confirmed that with increasing the amount of nanofillers, the tensile strength and elastic modulus increased, while the elongation-at-break and impact strength decreased. By adding 5% (by wt) Cloisite to the polymer blend, the tensile strength and modulus increased by 18 and 23%, and elongation-at-break and impact strength decreased by 74 and 17%, respectively.

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Thermoplastic Vulcanizates of PBS- EVA and Cellulose Nanocrystal: a Comprehensive Experimental Study on the Mechanical, Rheological and Shape Memory Behavior

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Journal of polymers and the Environment 2025年 1-17页

作者： Nourany, Mohammad Aminyan, Reyhaneh Fahimi, Mahtab Kargaran, Farshad Alghazali, Sundus Mahdi Department of Polymer Engineering and Color Technology Amirkabir University of Technology Tehran Iran Department of Polymer Engineering Petroleum and Chemical Engineering Faculty Science and Research Branch Islamic Azad University Tehran Iran Department of Polymer Processing Iran Polymer and Petrochemical Institute Tehran Iran Department of Prosthetics and Orthopedics Engineering University of Kerbala Kerbala Iraq

Poly (butylene succinate) (PBS) is among the least studied biodegradable polyesters, where its high crystallinity and low extensibility had limited its wide- spread application for packaging. In this work, we designed a series of thermoplastic elastomers (TPEs) and vulcanizates (TPVs) based on PBS and ethylene vinyl acetate (EVA) with a focus on its modulus ( $$\:E$$ ) and elongation at break ( $$\:{\epsilon\:}_{b}$$ ). The TPEs showed poor mechanical performance and using dicumyl peroxide (DCP), applied directly (D) and as a masterbatch with EVA (M), resulted in superior mechanical performance with the TPV based on the PBS: EVA composition of 90: 10-D showing the highest $$\:{\epsilon\:}_{b}$$ of 637.6% compared to the $$\:{\epsilon\:}_{b}$$ of 108.1% for PBS. The $$\:E$$ value of the TPV was 139.1 MPa compared to 353.2 MPa for PBS, which was due to the presence of EVA rubber. However, presence of 2% cellulose nanocrystal (CNC) increased $$\:E$$ to 225.9 MPa with the $$\:{\epsilon\:}_{b}$$ of 463%. Both PBS and the optimal TPVs showed high shape fixity even at 25°C due to its high crystallinity, while the TPVs and especially, the TPV- CNC (2.0%) showed higher recovery ratios caused by formation of an elastic 3D network of both the cured EVA droplets and CNCs.

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Evaluating the Osmotic Effects on Shale Swelling and Proposing New Solutions

Evaluating the Osmotic Effects on Shale Swelling and Proposi...

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2025 SPE Conference at Oman Petroleum and Energy Show, OPES 2025

作者： Houshyar, A.A. Ebadi, A.M. Goaharpey, F. Dehvedar, M. Department of Polymer and Color Engineering Amirkabir University of Technology Tehran Iran Department of Petroleum and Geoenergy Engineering Amirkabir University of Technology Tehran Iran

ISBN: (纸本)9781959025740

The instability of wellbores in shale formations poses a significant challenge in the drilling industry. Water and ions move through shale via different complex mechanisms, leading to wellbore instability. This study explores the effectiveness of specific materials, including synthetic nanoparticles, in enhancing shale stability by sealing pores and reducing osmotic pressure infiltration. In this study, seven categories of bentonite mud ranging from 2% to 8%, as well as four combined categories of bentonite and nanoparticles, were prepared and examined. Additionally, the rheological properties of the fluid, the elastic phase, and the viscous phase as a function of frequency were measured for both groups, and the corresponding graphs were plotted. Both fluids followed the Herschel-Bulkley model, and the viscosity of the drilling fluid was plotted against frequency and shear rate. The experiments demonstrated that integrating nanoparticles into drilling fluids significantly improves wellbore stability by reducing the thickness of mud cakes and the filtrate volume. These nanoparticles effectively seal the shale pores, minimizing osmotic pressure infiltration, as evidenced by SEM images showing suitable adhesion to bentonite shale particles. This adhesion can be attributed to the role of substituent groups on the nanoparticles. SA nanoparticles improved the stability of shale formations. It can significantly reduce shale swelling by forming a barrier on the shale surface, which prevents water absorption. Adding it to drilling fluids enhances their rheological properties, making them more stable and effective at carrying cuttings to the surface. SA Nanoparticles can improve shale formations' performance and stability. Copyright 2025, Society of Petroleum Engineers.

关键词： Drilling platforms

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Interface Localization of Reduced Graphene Oxide in Polystyrene/Polymethyl Methacrylate Blends with Co-Continuous Morphology: Investigating the Effects of polymer Interface on Nanoparticle Network Stabilization

SSRN

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SSRN 2023年

作者： Negaresh, Mohammadmahdi Javadi, Azizeh Garmabi, Hamid Department of Polymer Engineering and Color Technology Amirkabir University of Technology Tehran Iran

In this study, the co-continuous morphology of polymer blends was investigated to determine if nanoparticles could be localized at the interface of polymers to form a well-organized network and decrease their percolation threshold. Solution-mixed polystyrene (PS)/polymethyl methacrylate (PMMA) blends containing reduced graphene oxide (rGO) were chosen and samples were analyzed for rheological, electrical, dynamic-mechanic properties, topography, and morphology. The graphene oxide in different degrees of thermal reduction was prepared, and the range of rGO thermal reduction that the particles tend to lie at the interface was detected according to surface tension measurements. The required amount of rGO to cover the total polymers interface of co-continuous blend was determined to be about 0.1 wt.% of volume basis on the electrical characterization. The rheology time sweep demonstrates that even though the initial storage modulus of the nanocomposite containing interface located particles is almost equal to the sample with randomly distributed particles, the upward changes of the storage modulus increases over time with a smaller slope, and it attains a smaller final value. All of the results prove that the flocculation of rGO particles reduces, as they are located at the interface. © 2023, The Authors. All rights reserved.

关键词： Polystyrenes

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“Interface localization of reduced graphene oxide in polystyrene/polymethyl methacrylate blends with co-continuous morphology: Investigating the effects of polymer interface on nanoparticle network stabilization”

Results in Materials

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Results in Materials 2024年 21卷

作者： Negaresh, Mohammadmahdi Javadi, Azizeh Garmabi, Hamid Amirkabir University of Technology Department of Polymer Engineering and Color Technology Tehran Iran

This study aimed to investigate the co-continuous morphology of polymer blends and determine whether nanoparticles can be localized at the interface of polymers to create a well-organized network and decrease the percolation threshold. The researchers chose solution-mixed polystyrene (PS)/polymethyl methacrylate (PMMA) blends containing reduced graphene oxide (rGO) for analysis of their rheological, electrical, dynamic-mechanic properties, topography, and morphology. Graphene oxide in varying degrees of thermal reduction was prepared, and surface tension measurements were used to detect the range at which the particles tend to reside at the interface. Based on electrical characterization, it was determined that the required amount of rGO to cover the total polymer interface in the co-continuous blend is approximately 0.1 wt% on a volume basis. The rheology time sweep revealed that, while the initial storage modulus of the nanocomposite containing interface-located particles is similar to that of the sample with randomly distributed particles, the increase in storage modulus over time is less steep, resulting in a lower final value. These findings confirm that the flocculation of rGO particles decreases when they are located at the interface. © 2023 The Authors

关键词： Co-continuous Nanoparticle network polymer interface Polymethyl methacrylate Polystyrene

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