Thin-film composite (TFC) membranes containing various fillers and additives present an effective alternative to conventional dense polymer membranes, which often suffer from low permeance (flux) and the permeability-selectivity tradeoff. Alongside the development and utilization of numerous new polymers over the past few decades, diverse additives such as metal-organic frameworks (MOFs), graphene oxides (GOs), and ionic liquids (ILs) have been integrated into the polymer matrix to enhance performance. However, achieving desirable interfacial compatibility between these additives and the host polymer matrix, particularly in TFC structures, remains a significant challenge.
View Article and Find Full Text PDFGiven the environmental concerns surrounding fluoromaterials, the use of high-cost perfluorinated sulfonic acids (PFSAs) in fuel cells and water electrolysis contradicts the pursuit of clean energy systems. Herein, we present a fluorine-free dumbbell-shaped block-graft copolymer, derived from the cost-effective triblock copolymer, poly(styrene-b-ethylene-co-butylene-b-styrene) (SEBS), for polymer electrolyte membranes (PEMs). This unique polymer shape led to the alignment of the hydrophobic-hydrophilic domains along a preferred orientation, resulting in the construction of interconnected proton channels across the membrane.
View Article and Find Full Text PDFOrthod Craniofac Res
December 2024
Objectives: Since developing AI procedures demands significant computing resources and time, the implementation of a careful experimental design is essential. The purpose of this study was to investigate factors influencing the development of AI in orthodontics.
Materials And Methods: A total of 162 AI models were developed, with various combinations of sample sizes (170, 340, 679), input variables (40, 80, 160), output variables (38, 76, 154), training sessions (100, 500, 1000), and computer specifications (new vs.
The effects of the operating conditions, including the applied pressure, feed organic concentration, and recirculation flowrate along the TiO-coated ceramic membrane, on the normalized membrane permeability and organic removal efficiency were systematically investigated by operating a photocatalytic membrane reactor (PMR). Response surface methodology (RSM) was conducted to better understand the interactive effect of operational conditions as well as their individual and combined effects to control membrane performance. Our results showed that the applied pressure and feed organic concentration, as single parameter, affected the normalized membrane permeability and organic removal efficiency more dominantly than the recirculation flowrate.
View Article and Find Full Text PDFChem Commun (Camb)
February 2024
A reverse method involves the pre-formation of an Matrimid (MI)-selective layer, followed by a porous polysulfone (PSF) support deposition. The membrane exhibited a high H/CH selectivity and a moderate H permeance. This study introduces a facile method to produce membranes with inexpensive materials.
View Article and Find Full Text PDFNeat poly(vinylidene fluoride) (PVDF) ultrafiltration (UF) membranes exhibit poor water permeance and surface hydrophobicity, resulting in poor antifouling properties. Herein, we report the synthesis of a fluorine-containing amphiphilic graft copolymer, poly(2,2,2-trifluoroethyl methacrylate)--poly(ethylene glycol) behenyl ether methacrylate (PTFEMA--PEGBEM), hereafter referred to as PTF, and its effect on the structure, morphology, and properties of PVDF membranes. The PTF graft copolymer formed a self-assembled nanostructure with a size of 7-8 nm, benefiting from its amphiphilic nature and microphase separation ability.
View Article and Find Full Text PDFThin-film composite mixed-matrix membranes (TFC-MMMs) have potential applications in practical gas separation processes because of their high permeance (gas flux) and gas selectivity. In this study, we fabricated a high-performance TFC-MMM based on a rubbery comb copolymer, i.e.
View Article and Find Full Text PDFGeneration of water as a byproduct in chemical reactions is often detrimental because it lowers the yield of the target product. Although several water removal methods, using absorbents, inorganic membranes, and additional dehydration reactions, have been proposed, there is an increasing demand for a stable and simple system that can selectively remove water over a wide range of reaction temperatures. Herein we report a thermally rearranged polybenzoxazole hollow fiber membrane with good water permselectivity and stability at reaction temperatures of up to 400 °C.
View Article and Find Full Text PDFEngineering thermoplastics, such as poly(arylene ether sulfone), are more often synthesized using F-containing monomers rather than Cl-containing monomers because the F atom is considered more electronegative than Cl, leading to a better condensation polymerization reaction. In this study, the reaction's spontaneity improved when Cl atoms were used compared to the case using F atoms. Specifically, sulfonated poly(arylene ether sulfone) was synthesized by reacting 4,4'-dihydroxybiphenyl with two types of biphenyl sulfone monomers containing Cl and F atoms.
View Article and Find Full Text PDFNanomaterials (Basel)
November 2021
With the increasing energy demand for portable electronics, electric vehicles, and green energy storage solutions, the development of high-performance supercapacitors has been at the forefront of energy storage and conversion research. In the past decade, many scientific publications have been dedicated to designing hybrid electrode materials composed of vanadium pentoxide (VO) and carbon nanomaterials to bridge the gap in energy and power of traditional batteries and capacitors. VO is a promising electrode material owing to its natural abundance, nontoxicity, and high capacitive potential.
View Article and Find Full Text PDFThis review addresses composite membranes used for wastewater treatment, focusing heavily on the anti-biofouling properties of such membranes. Biofouling caused by the development of a thick biofilm on the membrane surface is a major issue that reduces water permeance and reduces its lifetime. Biofilm formation and adhesion are mitigated by modifying membranes with two-dimensional or zero-dimensional carbon-based nanomaterials or their modified substituents.
View Article and Find Full Text PDFNanosheets are important structures usually composed of inorganic materials, such as metals, metal oxides, and carbon. Their creation typically involves hydrothermal, electrochemical or microwave processes. In this study, we report a novel formation mechanism of 3D polymer nanosheets facile solution casting using a comb copolymer consisting of poly(ethylene glycol) behenyl ether methacrylate and poly(oxyethylene) methacrylate (PEGBEM-POEM).
View Article and Find Full Text PDFAlcohol-soluble comb copolymers were synthesized from rubbery poly(oxyethylene methacrylate) (POEM) and glassy polyacrylamide (PAcAm) via economical and facile free-radical polymerization. The synthesis of comb copolymers was confirmed by Fourier-transform infrared and proton nuclear magnetic resonance spectroscopic studies. The bicontinuous microphase-separated morphology and amorphous structure of comb copolymers were confirmed by wide-angle X-ray scattering, differential scanning calorimetry, and transmission electron microscopy.
View Article and Find Full Text PDFWe prepare dye-sensitized solar cells (DSSCs) fabricated with a poly (ethylene glycol) based polymer gel electrolytes (PGEs) incorporating surface carbon shell-functionalized ZrO nanoparticles (ZrO-C) as nanofillers (NFs). ZrO are polymerized via atom transfer radical polymerization (ATRP) using poly (ethylene glycol) methyl ether methacrylate (POEM) as a scaffold to prepare the ZrO-C through carbonization. The power conversion efficiency of DSSC with 12 wt% ZrO-C/PGEs is 5.
View Article and Find Full Text PDFEpoxy foam adhesives are widely used for weight reduction, watertight property, and mechanical reinforcement effects. However, epoxy foam adhesives have poor impact resistance at higher expansion ratios. Hence, we prepared an epoxy composite foam adhesive with core⁻shell rubber (CSR) particles to improve the impact resistance and applied it to automotive structural adhesives.
View Article and Find Full Text PDFIn this study, we combined enzymatic hydrolysis and lactic acid fermentation to generate an antihypertensive product. Soybean protein isolates were first hydrolyzed by Prozyme and subsequently fermented with EBD1. After fermentation, the in vitro angiotensin-converting enzyme (ACE) inhibitory activity of the product (P-SPI) increased from 60.
View Article and Find Full Text PDFThe structural orientation of an amphiphilic crystalline polymer to a highly ordered microphase-separated lamellar structure on a hydrophobic surface is presented. It is formed by the surface graft polymerization of poly(ethylene glycol)behenyl ether methacrylate onto poly(trimethylsilyl) propyne in the presence of allylamine. In particular, allylamine plays a pivotal role in controlling the crystalline phase, configuration, and permeation properties.
View Article and Find Full Text PDFBattery performance, such as the rate capability and cycle stability of lithium transition metal oxides, is strongly correlated with the surface properties of active particles. For lithium-rich layered oxides, transition metal segregation in the initial state and migration upon cycling leads to a significant structural rearrangement, which eventually degrades the electrode performance. Here, we show that a fine-tuning of surface chemistry on the particular crystal facet can facilitate ionic diffusion and thus improve the rate capability dramatically, delivering a specific capacity of ∼110 mAh g at 30C.
View Article and Find Full Text PDFA major challenge in the industrial use of enzymes is maintaining their stability at elevated temperatures and in harsh organic solvents. In order to address this issue, we investigated the use of nanotubes as a support material for the immobilization and stabilization of enzymes in this work. SnO hollow nanotubes with a high surface area were synthesized by electrospinning the SnCl precursor and polyvinylpyrrolidone (dissolved in dimethyl formamide and ethanol).
View Article and Find Full Text PDFThe decoration of porous membranes with a dense layer of nanoparticles imparts useful functionality and can enhance membrane separation and anti-fouling properties. However, manufacturing of nanoparticle-coated membranes requires multiple steps and tedious processing. Here, we introduce a facile single-step method in which bicontinuous interfacially jammed emulsions are used to form nanoparticle-functionalized hollow fiber membranes.
View Article and Find Full Text PDFA simple and flexible strategy for controlled synthesis of mesoporous metal oxide films using an amphiphilic graft copolymer as sacrificial template is presented and the effectiveness of this approach for gas-sensing applications is reported. The amphiphilic graft copolymer poly(vinyl chloride)-g-poly(oxyethylene methacrylate) (PVC-g-POEM) is used as a sacrificial template for the direct synthesis of mesoporous SnO. The graft copolymer self-assembly is shown to enable good control over the morphology of the resulting SnO layer.
View Article and Find Full Text PDFACS Appl Mater Interfaces
June 2017
Recently, the WO/BiVO heterojunction has shown promising photoelectrochemical (PEC) water splitting activity based on its charge transfer and light absorption capability, and notable enhancement of the photocurrent has been achieved via morphological modification of WO. We developed a graft copolymer-assisted protocol for the synthesis of WO mesoporous thin films on a transparent conducting electrode, wherein the particle size, particle shape, and thickness of the WO layer were controlled by tuning the interactions in the polymer/sol-gel hybrid. The PEC performance of the WO mesoporous photoanodes with various morphologies and the individual heterojunctions with BiVO (WO/BiVO) were characterized by measuring the photocurrents in the absence/presence of hole scavengers using light absorption spectroscopy and intensity-modulated photocurrent spectroscopy.
View Article and Find Full Text PDFNanomechanical characteristics of standalone silver nanowires (Ag NWs) are a key issue for providing a failure criterion of advanced flexible electrodes that are trending towards smaller radius of curvatures (ROCs). Through in-situ tensile and buckling tests of pentagonal Ag NWs, we demonstrated that the intrinsic fracture strain provides a significant criterion to predict the mechanical and electrical failure of Ag NW electrodes under various strain modes, because the decrease in fracture strain limits figure of merit of flexible devices. The Ag NW electrodes on a polymer substrate exhibited a strain-dependent electrical failure owing to the unique deformation characteristics with a size-dependent brittle-to-ductile transition of the five-fold twinned Ag NWs.
View Article and Find Full Text PDFWe present a feasible approach to the direct development of three-dimensionally (3D) bicontinuous gyroid (GYR) nanostructure in high-molecular-weight, composition-controlled polystyrene-b-poly(methyl methacrylate) (PS-b-PMMA) films. The use of a neutral solvent vapor to elaborately control the swelling of block copolymer (BCP) films is essential to generate a direct pathway to GYR (or giant GYR) structure through a hexagonal (HEX) cylindrical morphology in the same material, because the thermal ordering of highly entangled BCP imposes the limit on the chain mobility. Along with the improved mechanical strength arising from the high molecular weight property of the polymers, the structural integrity and overall excellence of a large-scale GYR morphology were confirmed by the results of membrane performance, which showed greater permeability through the nanoporous GYR structure up to by a factor of three than that through the HEX structure.
View Article and Find Full Text PDF