Polymer Bulletin (14362449)81(9)pp. 8331-8340
The new class of microfiltration (MF) membranes based on nanofibrous sub-layers was investigated in this study. To this end, polyethylene terephthalate (PET) nanofibrous layers were produced via electrospinning technique based on PET supports as baking material, and subsequently, the solvent vapor treatment was applied for pore size modification of nanofibrous membranes. Capillary flow porometry and scanning electron microscopy were used to evaluate of pore size and morphology of the membranes, respectively. Moreover, filtration performance was evaluated by water flux and microparticle/bacteria retention. The results showed that average pore size of PET electrospun nanofibrous membrane was greatly reduced from 1.2 to 0.4 µm during modification process. Solvent vapor-treated MF membranes show significantly higher flux and acceptable rejection compared to commercial MF membranes. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023.
Polymers for Advanced Technologies (10427147)35(11)
The primary aim of this project is to develop ultra-high expansion and quick-setting foams using poly (ethyl cyanoacrylate), poly (butyl cyanoacrylate), and poly (co-ethyl-butyl) cyanoacrylate. To achieve this, poly cyanoacrylate foams were created under various conditions, utilizing different monomers, initiators, foaming agents/solvents, and compositions. Several properties of the foams were assessed, including formation and expansion rates, mechanical strength, moisture absorption, thermal resistance, density, and morphology. The findings indicated that, under optimal conditions, the foams made from poly (ethyl cyanoacrylate), poly (butyl cyanoacrylate), and a copolymer of poly (ethyl cyanoacrylate-co-butyl cyanoacrylate) exhibited fast expansion times of approximately 0.9, 2, and 1.5 s, respectively. These foams demonstrated an average volume increase of about 35 times, 45 times, and 36 times compared to the raw materials. The average compressive strengths recorded were 6, 3, and 4 kg/cm2, while the average water absorption rates were 5%, 20%, and 7%, respectively. © 2024 John Wiley & Sons Ltd.
Cellulose (09690239)31(7)pp. 4395-4407
Separators are regarded as an essential component of lithium-ion batteries (LIBs) due to their critical roles in the electrochemical performance and safety of these batteries. The purpose of this study was to examine the structural and electrochemical properties of a new separator based on zwitterionic cellulose (Cell). The free radical polymerization method was used to graft 4-vinyl pyridinium propane sulfonate (4-VPPS) onto the hydroxyl groups of Cell, and the polymer solution in trifluoroacetic acid (TFA) solvent was prepared to form a thin membrane using an automatic film applicator. The results showed that the modified Cell (MCell) separator had significantly higher tensile strength and elastic modulus, as well as superior thermal and dimensional stability, when compared to control separators (polypropylene (PP) at transverse direction and unmodified Cell). The improved separator material effectively reduced the growth of lithium dendrites, which cause short circuits and battery failure. Furthermore, the zwitterionic Cell separator demonstrated improved cycling stability and rate capability. Overall, this study suggests that using MCell separators with 4-VPPS is a promising alternative for improving LIB performance. The findings help to advance battery technology by increasing safety, efficiency, and overall battery life. Graphical Abstract: (Figure presented.) © The Author(s), under exclusive licence to Springer Nature B.V. 2024.
Journal of Environmental Chemical Engineering (22133437)10(6)
Positively charged Nanofibrous nanofiltration (NF) membranes were prepared via multi-step interfacial polymerization from polyethylenimine (PEI) and terimesoyl chloride (TMC) on a polyurethane (PU) nanofibrous support. In this way, electrospinning technique was applied for preparation of the PU nanofibrous support and at the following, NF membranes were formed via layer-by-layer interfacial polymerization and the cycle of sequential depositions. The nanofibrous NF membranes were characterized using ATR-FTIR, surface charge, morphology, MWCO, capillary flow porometery and NF performance techniques. Moreover, the effect of the reaction cycle number on NF performance was evaluated. The result of NF membrane prepared by three cycles of reactions with 1.5 wt% PEI and 0.5 wt% TMC presented appropriate salt rejection and flux; 99.1% for MgCl2, 82.3% for MgSO4, 81% for NaCl and 57.1% for Na2SO4 and electrolyte permeate flux; 70 L/m2 h for MgCl2, 73 L/m2 h for MgSO4, 72 L/m2 h for NaCl and 74 L/m2 h for Na2SO4 under filtration pressure of 8 bar. At the end, the performance of positively TFNC-NF membrane was compared with other positively nanofiltration membranes. © 2022 Elsevier Ltd.
Journal of Polymers and the Environment (15662543)29(8)pp. 2463-2477
Polyurethane nanofibers recognized to perform as a sub-layer were employed herein as a medial-layer of high porosity in the fabrication of a novel class of thin-film nanofiltration membranes. In line with the primary aim of high throughput production of PU electrospun nanofibrous membranes (ENMs) with different fiber sizes and proper morphologies, the needle-free electrospinning technique was employed. An interfacial polymerization procedure was also utilized to conveniently coat a polyamide (PA) thin film on the polyurethane ENMs. The effects of the nanofibrous interconnecting network, fiber size, pore size, and morphology on the NF performance were investigated. The nanofiltration performance including the separation of various salts, water flux, and the MWCO test were performed. The results implied that the fiber size decrement, nanofibers interconnection increment, as well as nanofibrous membrane pore size decrement, and the nanofibrous layer increment (with different fiber size) would lead the interfacial polymerization to perfection and obtaining a uniform PA thin layer. The salts rejection and water flux of Na2SO4, MgSO4, MgCl2 and NaCl were (~ 99 ± 0.5 %, 37 ± 2.7 L/m2h), (~ 98 ± 1 %, 40 ± 1.5 L/m2h), (~ 95 ± 2 %, 33 ± 2 L/m2h) and (~ 52 ± 1 %, 30 ± 3 L/m2h), respectively. In the final analysis, a comparison of filtration performance between PU nanofibrous NF membranes with other well-known nanofibrous NF membranes was conducted. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC part of Springer Nature.
Fahimirad, S.,
Abtahi, H.,
Satei, P.,
Ghaznavi-rad, E.,
Moslehi, M.,
Ganji, A. Carbohydrate Polymers (18791344)259
In this study, the electrospun poly(ε-caprolactone) (PCL)/Chitosan (CS)/curcumin (CUR) nanofiber was fabricated successfully with curcumin loaded chitosan nano-encapsulated particles (CURCSNPs). The morphology of the produced CURCSNPs, PCL, PCL/CS, PCL/CS/CUR, and PCL/CS/CUR electrosprayed with CURCSNPs were analyzed by scanning electron microscopy (SEM). The physicochemical properties and biological characteristics of fabricated nanofibers such as antibacterial, antioxidant, cell viability, and in vivo wound healing efficiency and histological assay were tested. The electrospraying of CURCSNPs on surface PCL/CS/CUR nanofiber resulted in the enhanced antibacterial, antioxidant, cell proliferation efficiencies and higher swelling and water vapor transition rates. In vivo examination and Histological analysis showed PCL/CS/CUR electrosprayed with CURCSNPs led to significant improvement of complete well-organized wound healing process in MRSA infected wounds. These results suggest that the application of PCL/CS/CUR electrosprayed with CURCSNPs as a wound dressing significantly facilitates wound healing with notable antibacterial, antioxidant, and cell proliferation properties. © 2021 Elsevier Ltd
Journal of Polymers and the Environment (15662543)28(10)pp. 2691-2701
Herein, the preparation of polyurethane nanofibrous microfiltration membranes, with electrospinning and then dip-coating methods was reported. The study of process parameters (i.e. needle-free electrospinning and dip-coating condition) on the membrane properties was also conducted. The different pore sizes of the prepared MF membranes (e.g. 0.23, 0.33, and 0.47 μm) is orchestrated through the adjustment of various electrospinning and dip-coating parameters. The capability of these membranes to simultaneously eliminate the sources of water pollution, i.e. micro-particles and bacteria, has been demonstrated. Specifically, the prepared membranes could thoroughly reject the E. coli BL21 (DE3) bacteria (~ 97–99%) as well as micro-particles through size extrusion mechanism (~ 95–99%), while they retained a high permeation flux (~ 65,400, ~ 40,000 and ~ 25,700 (L/m2 h bar) for 0.46, 0.33, and 0.25 μm pore size, respectively). In addition, a comparison between nanofibrous MF membranes and their commercial counterparts from both utility and effectiveness standpoint was conducted and the obtained result indicated the supreme performance of these membranes in comparison with the commercial membranes of the same mean pore size, also with almost double or triple higher flux. © 2020, Springer Science+Business Media, LLC, part of Springer Nature.
Separation and Purification Technology (13835866)223pp. 96-106
In this study, an avant-grade process for preparation of microfiltration membrane on the basis of a two-layered polyurethane (PU)/polyethylene terephthalate (PET) nanofibrous mat modified by multi-step interfacial polymerization was introduced. The effect of process parameters like monomer concentrations, reaction time, and the amount of reaction cycles, on the amount of polyamide formation (i.e. yield) were investigated. The pore sizes of the modified PU/PET electrospun nanofibrous based membranes, ranged in 0.25 and 0.46 μm, could be manipulated by these reaction parameters. These membranes have the capability to remove micro-particles and bacteria contamination simultaneously. In particular, the manufactured membrane could completely eliminate Stbl4 bacteria (∼98–99%) and micro-particles (∼96–99%) through size extrusion while maintaining a high permeation rate (∼46,500 (L/m2hbar) and ∼23,200 (L/m2hbar) for 0.46 μm and 0.25 μm, respectively). The performance of these nanofibrous membranes was compared to their commercial competitors. The results highlighted that the modified nanofibrous membranes represented superior twice/treble higher flux filtration performance in comparison with the commercial ones of the similar mean pore size. The extension mechanism of fibrous membranes was founded on the evolution of a webbed and spider webby architecture featuring a large surface area per volume for the exclusion and adsorption of contaminant particles. © 2019 Elsevier B.V.
Journal of Polymer Research (15728935)23(12)
The main objective of this study was to prepare thin film nanofibrous composite (TFNC) membranes based on self-support nanofibrous mats. To this end, polyethylene terephthalate nanofibrous supports were produced by electrospinning technique and subsequently heat treatment was performed to increase mechanical stability of the mats. Then, interfacial polymerization procedure was applied for preparation of TFNC nanofiltration membranes. For comparison, the thin film composite (TFC) nanofiltration membrane was prepared by the same conditions based on polyethersulfone ultrafiltration membrane prepared through phase inversion method. Chemical structure, morphology and mechanical properties were studied by using ATR-FTIR, SEM and tensile tests, respectively. Also, filtration performance was investigated by water flux, rejection, water contact angle and MWCO determination. Results showed that the TFNC nanofiltration membrane had higher salt rejection and four times higher water flux than the TFC nanofiltraion membrane (Na2SO4 rejection and pure water flux were (93 ± 3)%, (34 ± 2.3) L./m2h and (67 ± 4)%, (8 ± 0.9) L./m2h for TFNC and TFC, respectively). At the end, the filtration performance of PET TFNC-NF membrane was compared with other nanofibrous nanofiltration membranes. [Figure not available: see fulltext.] © 2016, Springer Science+Business Media Dordrecht.
