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This study includes the fabrication of highly sulfonated polyethersulfone (SPES)/polyethersulfone (PES) blended membranes with superior properties for effective oil/water separation. In this regard membranes with different content of SPES and degree of sulfonation (DS) were fabricated. Highly sulfonated PES was synthesized by chlorosulfonic acid and concentrated sulfuric acid at low temperature. FTIR and DS analysis confirmed the presence of sulfonic acid groups on the PES backbone. The phase inversion process of membrane fabrication was studied by ternary phase diagram construction and dope solutions viscosity measurement. Fabricated membranes were characterized by SEM, water contact angle, porosity, pure water flux, and mechanical strength. The SEM images demonstrated that blended membranes have wider finger-like pores in their structure compared to bare PES membrane. Results indicated that by increasing SPES content and DS, permeability increased but mechanical strength decreased. The membranes fabricated by 50% SPES with 37% DS and 50% PES has the highest permeability (59.89 l/m2.h) with 93.3% oil rejection. Also antifouling properties of blended membranes improved remarkably compared to PES membrane.

Polydopamine has been widely used as an additive to enhance membrane fouling resistance. This study reports the effects of two-step dopamine-to-polydopamine modification on the permeation, antifouling, and potential anti-UV properties of polyethersulfone (PES)-based ultrafiltration membranes. The modification was performed through a two-step mechanism: adding the dopamine additive followed by immersion into Tris-HCl solution to allow polymerization of dopamine into polydopamine (PDA). The results reveal that the step of treatment, the concentration of dopamine in the first step, and the duration of dipping in the Tris solution in the second step affect the properties of the resulting membranes. Higher dopamine loadings improve the pure water flux (PWF) by more than threefold (15 vs. 50 L/m2·h). The extended dipping period in the Tris alkaline buffer leads to an overgrowth of the PDA layer that partly covers the surface pores which lowers the PWF. The presence of dopamine or polydopamine enhances the hydrophilicity due to the enrichment of hydrophilic catechol moieties which leads to better anti-fouling. Moreover, the polydopamine film also improves the membrane resistance to UV irradiation by minimizing photodegradation’s occurrence.

High‐performance electrodes based on carbonaceous nanomaterials are pivotal for several electrochemical applications that require interfaces with enhanced kinetics. In this study, we report an innovative approach to develop composite membranes for producing laser‐engineered graphene electrodes (LEGEs) for electrochemical sensing. Composite membranes were prepared by blending aminated polyethersulfone (H2N‐PES) with carbon black (CB) at different weight ratios (0.1, 0.2, and 0.3 wt%). The resulting composite membranes served as scaffolds for preparing LEGEs. Both the composite membranes and the derived LEGEs were thoroughly characterized using spectroscopic, thermal, electrochemical, and scanning electron miscroscopy  techniques. The results showed that the incorporation of CB into the polymer substantially enhanced the electrochemical performance compared to the pristine H2N‐PES membrane, particularly for the membrane containing 0.3 wt% loading of CB; it can be used for ascorbic acid determination in the concentration range of 10–300 µM with a detection limit of 2.45 µM, with high selectivity over uric acid and dopamine. LEGEs were successfully applied for the selective electrochemical sensing of ascorbic acid in spiked solutions and in commercial orange juice samples. Novel laser‐engineered graphene electrodes from low‐cost polyether sulfone membranes for the sensitive chemoselective sensing of bioactive molecules.

The development of high-performance polymer membranes has sparked a lot of attention in recent years. Polymer blending is a potential method of modification. A limitation, however, is the compatibility of blends at the molecular level. In this investigation, polyethersulfone/polyetherimide hollow fiber membranes were prepared by the solution blending method. Compatibility, hydrogen bonding, crystallinity, microstructure, hydrophilicity, mechanical properties, and transmissibility of blended membranes were also characterized. The compatibility and hydrogen bonding action of the two components were confirmed by DSC, FTIR, XPS, and XRD. The structure exhibits a C−H···O interaction motif with the sulfone group acting as a hydrogen bond acceptor from a methyl C−H donor. The π–π stacking between the two polymers arranged molecules more orderly, resulting in enhanced intermolecular interactions. Compared to polyethersulfone hollow fiber membranes, the hydrophilic, mechanical properties, and rejection rate of the blended membranes are more effectively enhanced. Self-assembly of the host polymer with a polymer capable of forming hydrogen bonds to construct controllable blends is a crucial and proven method.

In order to address the limitation of low flux in ultrafiltration (UF), a suitable additive is introduced into the base polymer to modify the membrane morphology, thereby enhancing flux rates. In this study, chamomile leaf nanoparticles (Chm NPs) were investigated as a novel green material for utilizing in UF membrane synthesizes. To enhance comprehension of the influence of Chm on the synthesis of PES UF membranes, a series of membranes were fabricated by including different quantities of Chm into the casting solution; (0, 0.5, 1.5, and 2 wt. %.). The synthesized membranes were fully characterized, through the porosity, pore size, hydrophilicity, membrane morphology, and UF efficiency. Manufactured PES/Chm membranes demonstrated significantly increased permeate water flux (PWF) (up to 498 kg/m2 h), which was four times that of the pristine PES membrane (116 kg/m2 h), besides that the bovine serum albumin (BSA) and Congo red dye (CR) rejection of PES/Chm membranes was still kept high. The enhanced PWF was mostly due to the more porous membrane structure and increased hydrophilicity. Meanwhile, the higher surface hydrophilicity of the PES/Chm membranes resulted in greater antifouling performance and the high flux recovery ratio (FRR) of 93 %. Based on the results of this research, the Chm may be used as a novel green additive with substantial application potential in the fabrication of UF membranes wastewater treatment.

Useful materials must satisfy multiple objectives, where the optimization of one objective is often at the expense of another. The Pareto front reports the optimal trade-offs between these conflicting objectives. Here we use a self-driving laboratory, Ada, to define the Pareto front of conductivities and processing temperatures for palladium films formed by combustion synthesis. Ada discovers new synthesis conditions that yield metallic films at lower processing temperatures (below 200 °C) relative to the prior art for this technique (250 °C). This temperature difference makes possible the coating of different commodity plastic materials (e.g., Nafion, polyethersulfone). These combustion synthesis conditions enable us to to spray coat uniform palladium films with moderate conductivity (1.1 × 10 5  S m −1 ) at 191 °C. Spray coating at 226 °C yields films with conductivities (2.0 × 10 6  S m −1 ) comparable to those of sputtered films (2.0 to 5.8 × 10 6  S m −1 ). This work shows how a self-driving laboratoy can discover materials that provide optimal trade-offs between conflicting objectives. Useful materials must satisfy multiple objectives. The Pareto front expresses the trade-offs of competing objectives. This work uses a self-driving laboratory to map out the Pareto front for making highly conductive coatings at low temperatures.

In this study, the mechanical and thermophysical properties of carbon fiber-reinforced polyethersulfone are investigated. To enhance the interfacial interaction between carbon fibers and the polymer matrix, the surface modification of carbon fibers by thermal oxidation is conducted. By means of AFM and X-ray spectroscopy, it is determined that surface modification changes the morphology and chemical composition of carbon fibers. It is shown that surface modification dramatically increases the mechanical properties of the composites. Thus, flexural strength and the E-modulus of the composites reinforced with modified fibers reached approximately 962 MPa and 60 GPa, respectively, compared with approximately 600 MPa and 50 GPa for the composites reinforced with the initial ones. The heat deflection temperatures of the composites reinforced with the initial and modified fibers were measured. It is shown that composites reinforced with modified fibers lose their stability at temperatures of about 211 °C, which correlates with the glass transition temperature of the PES matrix. The thermal conductivity of the composites with different fiber content is investigated in two directions: in-plane and transverse to layers of carbon fibers. The obtained composites had a relatively high realization of the thermal conductive properties of carbon fibers, up to 55–60%.

The possibility of replacing traditional toxic solvents normally employed during the preparation of polymeric membranes with greener alternatives represents a great challenge for safeguarding the human health and protecting the environment. In this work, an improved and pleasant-smelling version of dimethylsulfoxide (DMSO), i.e., DMSO EVOL™, was used as “greener solvent” for the preparation of polyethersulfone (PES) microfiltration (MF) membranes using a combination of non-solvent and vapor-induced (NIPS and VIPS, respectively) phase separation technique for the first time. The effect of two different additives polyvinylpyrrolidone (PVP) and poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (Pluronic®) together with polyethylene glycol (PEG) on membrane properties and performances has been also evaluated. The membranes were characterized in terms of morphology, mechanical resistance, pore size, and water permeability. The obtained results show that DMSO EVOL™ is able to replace 1-methyl-2-pyrrolidone (NMP), which is a more toxic solvent normally used for the preparation of PES membranes. Furthermore, it was possible to tune the produced membranes in the range of MF (0.1–0.6 μm).

The advancement of technologies for producing chemicals and materials from non‐fossil resources is of critical importance. An illustrative example is the dehydrogenation of glucose, to yield gluconic acid, a specialty chemical. In this study, we propose an innovative production route for gluconic acid while generating H2 as a co‐product. Our concept involves a dual‐function membrane, serving both as a catalyst for glucose dehydrogenation into gluconic acid and as a means to efficiently remove the produced H2 from the reaction mixture. To achieve this two membranes were developed, one catalytically active and one dense aimed at H2 removal. The catalytic membrane showed significant activity, yielding 16 % gluconic acid (t=120 min) with a catalyst selectivity of 93 % and stable performance over five consecutive cycles. Incorporating the H2 separating membrane showed the significance of H2 removal in driving the reaction forward. Its inclusion led to a twofold increase in gluconic acid yield, aligning with Le Chatelier's principles. As a future prospect the two layers can be combined into a dual‐layer membrane which opens the way for a new production route to simultaneously produce gluconic acid and H2, using high‐throughput reactors such as hollow‐fiber systems. This work provides a proof of concept of a two‐membrane system for the catalytic dehydrogenation of glucose to gluconic acid. One is a catalytic active mixed matrix membrane (incorporation of Pt‐CNF) that has a high selectivity towards gluconic acid (93 %). The other is a H2 separating membrane with the goal of removing H2 from the reaction mixture, thereby disrupting the equilibrium and driving the reaction forward.

Interfacial interaction is one of the most important factors that affect the mechanical properties of the fiber reinforced composites. The effect of fabrics′ sizing removal from glass fibers’ surface by thermal treatment on the mechanical characteristics of polyethersulfone based composites at different fiber to polymer weight ratios was investigated. Three fiber to polymer weight ratios of 50/50, 60/40, and 70/30 were studied. Flexural and shear tests were carried out to illustrate the mechanical properties of the composites; the structure was studied using Fourier-transform infrared spectroscopy and scanning electron microscopy. It was shown that solution impregnation of glass fabrics with polyethersulfone before compression molding allows to achieve good mechanical properties of composites. The thermal treatment of glass fabrics before impregnation results in an increase in flexural and shear strength for all the composites due to the improvement of fiber–matrix interaction.