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This study investigated the effects of different braid materials (polyethylene terephthalate, nylon 6, and their hybrid), weaving frequencies of the braids (7, 9, 11, 13 Hz), and concentrations of polyether sulfone solution (15% and 18 wt%) on braid angles, braid thickness, and bursting resistance. The results showed that for all types of single and hybrid braids, the braid angle decreases with increasing spinning frequency. When spinning frequency was increased from 7 to 13 Hz, the average wall thickness of polyethylene terephthalate, nylon 6, and the hybrid braids increased by approximately 50%, 65%, and 60%, respectively. The bursting pressure results were obtained in the range of 9.3 to 20.2 bars. The Fourier transform infrared spectroscopy results revealed no chemical bond between the braids and the polyether sulfone layer. Optical and electron microscope analyses revealed formation of uniform thickness of the polyether sulfone layers on the surface of the braids, as well as the penetration of polyether sulfone into the gaps between the filaments. The analyses also showed macroscopic adhesion of polyether sulfone to the braids and provided information on the amount and size of the pores in the polymer layers. The results showed that the selection of appropriate weaving frequency, braid materials, and polyether sulfone layer concentration are important as controllable parameters for producing polymeric hollow fiber composites with excellent burst pressure resistance. [ABSTRACT FROM AUTHOR]

• Real industrial mixtures of 12 components were separated by PV using MSE membranes. • Aromatics were recovered from their mixture with alicyclics/aliphatics/alcohols. • Methanol contamination negatively affects aromatic recovery via coupling effect. • Membrane plasticization by aromatics is intensified by methanol contamination. • Benzene has stronger coupling effects on n-hexane/cyclohexane compared to toluene. The pervaporation separation of aromatics from real industrial multicomponent mixtures containing 12 aromatic/alicyclic/aliphatic/alcoholic compounds was investigated using MSE polymer membranes. The effects of operating parameters including temperature, flow rate, permeate pressure, total aromatic content, and methanol contamination on PV performance were investigated. The behavior of the membrane in terms of swelling, plasticization and coupling effect in contact with real industrial multicomponent feed was evaluated and the work was completed by finding how the operating parameters influence the mass transfer mechanisms, component activity, dominant and limiting transfer phenomena, and coupling effect. The results showed that methanol contamination weakened the positive influences of increasing temperature and reducing permeate pressure. The coupling effects between benzene/toluene as fast-permeating components on n-hexane/cyclohexane as slow-permeating components in the presence of methanol were investigated. The results revealed that benzene has a stronger kinetic coupling effect on n-hexane and cyclohexane than toluene has. Furthermore, the coupling effect is more effective on n-hexane than cyclohexane. The results also showed that the presence of a second fast-permeating component (methanol) typically enhances the permeation of slow-permeating species. In general, the coupling effect had a negative effect on the PV performance in this work which favors the aromatic recovery. [ABSTRACT FROM AUTHOR]

In emergency treatment research, the focus on chitosan-based products for wound healing has been consistent. This study specifically explores a dressing made by mixing chitosan (CS) and poly (vinyl alcohol) PVA. Using electrospinning technology, nanofiber membranes of CS and PVA are created with the assistance of non-toxic and hydrophilic polyethylene oxide (PEO). The outcome is a new nanofibrous membrane loaded with mupirocin, designed for healing burn wounds. The study delves into the influence of PVA, CS, and PEO concentrations on the structural and chemical characteristics of the mats. This comprehensive exploration involves techniques such as Scanning Electron Microscope (SEM), Atomic Force Microscopy (AFM) imaging, Fourier Transform Infrared Spectrometry (FTIR analysis), and Contact angle measurements. Additionally, the research evaluates the antibacterial performance and biomedical behavior of the developed scaffolds. PEO proves beneficial in the electrospinning process, contributing to smoother fibers. Meanwhile, the addition of CS and mupirocin leads to formation of the thinner nanofibers (251 ± 5 μm and 263 ± 4 μm, respectively) and scaffolds with higher swelling (up to ∼3.5 times at 90 min). Notably, the (MTT) assay confirms the non-cytotoxicity of the fabricated nanofibers, with proliferations exceeding ∼85% for all samples. The crosslinked samples released the drug more slowly than the non-crosslinked dressings, with 80% of the scaffolds releasing the drug within 24 h. The in-vivo investigations suggested that the drug-containing scaffolds performed reliably and showed promise as a medical dressing for treating burn wounds. • Mupirocin was incorporated into the nanofibers made from the blending of PEO, PVA, and CS. • This exploration involves techniques such as SEM, AFM imaging, FTIR analysis, and Contact angle measurements. • The developed nanofiber membranes exhibited no cytotoxicity. • The drug loaded nanofibers showed excellent antibacterial and wound healing behaviors. [ABSTRACT FROM AUTHOR]

Biopolymer-based electrospun mats, mimicking the extracellular matrix, have been extensively explored in biomedical applications. This study compares Achillea millefolium (AM) and Viola (V) extracts for developing a biocompatible wound dressing. The extracts were incorporated into a Chitosan/polyvinyl alcohol (CS/PVA) matrix via electrospinning. Crosslinking with Carbonyldiimidazole (CDI) improved chemical stability, water resistance, and biodegradability. The resulting mats exhibited flawless interconnected nanofibers, confirming the presence of AM and Viola extracts as analyzed via FTIR. Significant differences were observed between these two herbal extracts, particularly in mechanical properties, with tensile strengths of 6.9 MPa for AM and 17.2 MPa for Viola. Viola extract demonstrated robust antibacterial properties, producing an 8.2 mm inhibition zone against Staphylococcus aureus , compared to AM's 30 %. The release of therapeutic agents indicated an initial rapid phase, followed by a controlled 72 h release at a consistent rate. Notably, Viola extract led to 80.9 % wound closure on the 10th day, surpassing AM extract at 63.7 %. In contrast, the control group achieved only 32.1 % closure. This comparative study underscores the distinct advantages of AM and Viola extracts in wound dressing applications. While AM presents specific strengths, Viola extract exhibits superior mechanical properties, antibacterial efficacy, and accelerated wound closure, suggesting its potential with significant clinical implications. [Display omitted] • Achillea millefolium (AM) and Viola (V) extracts were obtained. • CS/PVA/AM (CPAM) and CS/PVA/V (CPV) mats were fabricated by electrospinning. • Morphology and in-vitro behavior were studied after Carbonyldiimidazole crosslinking. • The mat's antibacterial activity was significantly improved by adding the Viola extract. • The optimized dressings showed favorable biocompatibility and wound regeneration. [ABSTRACT FROM AUTHOR]

Membrane bioreactors (MBRs) as biotechnology-based wastewater treatment processes have recently attracted lots of attentions. However, membrane fouling/biofouling as a significant obstacle has prevented MBRs from being widely used. The phase inversion method was used to fabricate a novel MIL-101(Cr) (MCPs)/polyethersulfone (PES) composite membrane. Adding MCPs up to 0.4 wt% significantly improved the membrane surface hydrophilicity and increased the membrane porosity, pore size, and fouling/biofouling formation resistance. Pure water flux of the optimal composite membrane increased by about 198.61% compared to the neat one. It also showed the lowest total fouling ratio (Rt: 48.79%) and irreversible fouling ratio (Rir: 10.43%), and the highest flux recovery ratio (FRR: 89.54%) and protein rejection (99%). Its COD removal efficiency for acetate as synthesis wastewater was about 75%. Performance of the optimal composite membrane was also evaluated at varied mixed liquor suspended solids (MLSS) concentrations of 8000, 10,000, and 12,000 mg/L. Increasing MLSS concentration decreased permeation flux due to rising sludge viscosity and fouling/biofouling formation. The results gave useful insights into preparation of hydrophilic composite membranes through blending of MCPs and PES to treat organic wastewaters using the MBR applications. [ABSTRACT FROM AUTHOR]