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This study aims to characterize and evaluate polyethylene oxide (PEO) and chitosan (CS) nanofibers produced by electrospinning method. Electrospinning solutions were used at three different concentrations (1, 2, 3 wt%) with five different PEO/CS mixing ratios (30/70, 40/60, 50/50, 60/40, 100/0). FESEM, XRD and FTIR tests were applied for characterization of the nanofibers. Antibacterial activity of the nanofibers against Staphylococcus aureus and Klebsiella pneumoniae microorganisms was investigated using disk diffusion method. While 1 wt% of concentration was not suitable to obtain regular nanofibers, the nanofibers were uniform and largely free of beads at the other ones (2, 3 wt%). The average diameters of the nanofibers varied from 59 to 298 nm depending on the concentration and mixing ratio. Strong hydrogen bonds were formed between two polymers, while the crystal structure of PEO did not change significantly when mixed with chitosan. According to the study, whereas chitosan is resistant to a wide range of germs, PEO/CS nanofibers were not. The reason for this is because when chitosan is electrospun with PEO, the characteristics of the chitosan are altered by the concentrations and ratios used. [ABSTRACT FROM AUTHOR]

The demand for high-energy-density batteries has prompted exploration into advanced materials for enhancing the safety and performance of lithium metal batteries (LMBs). This study introduces a novel approach, incorporating two-dimensional (2D) pyrazine and imine-linked covalent organic frameworks (COFs) into a polyethylene oxide (PEO)-based solid electrolyte matrix. The synthesized COFs act as multifunctional additives, improving mechanical strength, ionic conductivity (reaching 1.86 ×10−3 S/cm at room temperature), electrochemical window (oxidation resistance up to 5 V vs. Li/Li+), and thermal stability (up to 400 °C). The unique electron-rich and polar functionalities of pyrazine and imine linkages facilitate strong interactions with lithium ions (Li+), resulting in a flexible composite solid electrolyte that mitigates dendrite formation and interface instability. Electrochemical performance of LMBs with LiNi 0.8 Mn 0.1 Co 0.1 O 2 (NMC811) cathode further confirm the enhanced Li+ conductivity, prolonged cycling stability, and a stable solid electrolyte interface, showcasing the potential of COFs in improving LMB performance. Overall, this study highlights the promising role of pyrazine and imine-linked COFs as effective additives for polymer-based solid electrolytes and their potential for developing safer and more efficient LMBs in the future. [Display omitted] • Significant increase in Li-ion conductivity in polymer electrolytes by incorporating 2D-COFs. • Optimal interaction between 2D-COFs and Li-ions facilitates fast ion transport. • Suppression of Li dendrite formation and good cycle stability with NMC811-based cells. • Incorporating COFs into polymer electrolytes is scalable and cost-effective. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Solid-state lithium metal batteries are one of the most promising candidates to take over the traditional liquid-based lithium ion batteries as they not only allow us to circumvent safety issues but also boost energy density far over the current limits imposed by the present chemistries. We have recently demonstrated that the combination of highly conductive inorganic solid electrolyte (ISE), Li0.33La0.55TiO3 (LLTO), with the mechanically durable solid polymer electrolyte (SPE), polyethylene oxide: Lithium bis (trifluoromethanesulfonyl)imide (PEO:LiTFSI), alongside a solid plasticizer, Succinonitrile, has proved to be successful in making highly performing polymer-rich (70% polymer) quaternary composite solid electrolytes (CSEs) that evade both the brittleness of ceramics and the poor conductivity of polymers. Herein, we extend the work to ceramic rich quaternary CSEs (70% ceramic). Ceramic-rich films were fabricated using tape casting technique and have reasonable ionic conductivity of 1.5 × 10−4 S cm−1 at 55 °C, decent mechanical properties and displays impressive endurance in Li ∣∣ Li symmetrical cells (> 800 h). Solid-state coin-type cells assembled with composite cathode show satisfactory cycling performance at 0.05 C and 55 °C reaching specific discharge capacity of 160.6 mAh g−1, maintaining high Coulombic efficiency (> 95%) and high capacity retention of 90.3% after 30 cycles. [ABSTRACT FROM AUTHOR]

We developed a composite membrane based on polyethylene oxide (PEO), achieving high CO 2 selectivity, by incorporating 7,7,8,8-tetracyanoquinodimethane (TCNQ)-modified CuO nanoparticles into the PEO matrix. The addition of TCNQ helps in evenly distributing the CuO nanoparticles throughout the membrane, preventing them from clumping together. This treatment not only enhances the dispersion of CuO particles but also imparts a positive charge to their surface, which is beneficial for increasing the selectivity for CO 2 over N 2. The extent of this surface charge modification on the CuO nanoparticles was evaluated using X-ray photoelectron spectroscopy (XPS), while the synergy between the polymer and the additives was verified through Fourier-transform infrared (FT-IR) spectroscopy studies. The combination of CuO nanoparticles in the membrane contributes to both barrier and carrier effects, enhancing the gas selectivity. This is further aided by the intrinsic properties of PEO, a rubber-like polymer known for its good gas permeance. As a result of these combined effects, the PEO/CuO/TCNQ membrane exhibited a remarkable CO 2 selectivity of 393 and a CO 2 permeance of 3.9 gas permeation unit (GPU). The superior separation performance of this membrane can be ascribed to three main factors: enhanced solubility due to the oxide layer on the particle surfaces and in the polymer matrix, improved transport efficiency via reversible interactions thanks to the positively charged surface, and the effective barrier provided by the nanoparticles against N 2 transport. These findings are expected to contribute significantly to future studies on the surface modification of metal nanoparticles and in the field of gas separation membranes. [Display omitted] • Modified surface energy of CuO by 7,7,8,8-tetracyano quinodimethane. • Accelerated gas transport on the surface of CuO. • Highly selective performance based on polymer composite. [ABSTRACT FROM AUTHOR]

As an eco-friendly alternative to the conventional anthraquinone process, electrochemical production of hydrogen peroxide (H 2 O 2) through the oxygen reduction reaction has been attracting attention. The goal of this work is to derive a carbon-based material from carbon dioxide (CO 2) to achieve high performance in electrochemical H 2 O 2 production. Doping heterogeneous element such as oxygen on a carbon catalyst has been mainly explored to increase the selectivity and activity, but little research has been conducted on enhancing catalytic activity with oxidized boron insertion. This study proposes porous carbon materials synthesized from CO 2 as electrocatalysts. Polyethylene oxide (PEO) was thermally treated together to increase the boron-oxygen bonding sites. As a result, the synthesized carbon materials having oxidized boron functional groups of BC 2 O and BCO 2 showed high activity (1.25 mA cm−2) and selectivity (∼90 %) over a wide voltage range in two-electron ORR (Oxygen Reduction Reaction) at alkaline media. Furthermore, in an H-cell where 0.4 V vs. RHE was applied, the average H 2 O 2 production rate was maintained at 452.96 mmol g−1 h−1 for four hours with a high faraday efficiency of 90 %. • Oxidized B-doped carbon was employed as an electrocatalyst for 2e- ORR. • The electrocatalyst was derived from CO 2 reduction. • B-doped configurations were varied through the thermal degradation of polymer. • Oxidized boron sites (BCO 2 and BC 2 O) are the most active for 2e- ORR. • The H-cell system marked enhanced H 2 O 2 selectivity (90 %) and productivity (452.96 mmol g−1 h−1). [ABSTRACT FROM AUTHOR]

All-solid-state Li-ion batteries, have become increasingly important because of their highly reliable solid electrolyte materials. Flexible solid polyethylene oxide (PEO) based electrolytes have been widely studied. Nevertheless, this material exhibits low lithium-ion conductivity. Herein, we report the optimisation of the composition of PEO/polyvinylidene fluoride (PVDF)-based electrolytes to enhance ionic conductivity. When the weight ratio of lithium bis(trifluoromethane sulphonyl)imide and PEO/PVDF is 1:5 (LiTFSI:PEO/PVDF = 1:5), maximum conductivities are 2.98 × 10−5 S cm−1 at 30°C and 5.56 × 10−4 S cm−1 at 60°C. Furthermore, the all-solid-state battery using this solid electrolyte film, a Li metal anode, and a LiFePO4 cathode delivers initial discharge capacities of 149.6 mAhg−1 (0.1 C, 60°C) and 130.2 mAh g−1 (0.5 C, 60°C). Meanwhile, the solid-state lithium battery also presents good cycling performance and excellent rate capability at 60°C. [ABSTRACT FROM AUTHOR]

High electrolyte-electrode interface stability is essential for solid state batteries to avoid side reactions that form interphases and voids, leading to loss of contact and increased impedance. Such detrimental situations increase overvoltage, reduce cycling efficiency, and shorten battery cycle life. While composite solid electrolytes were studied extensively, the effect of inorganic additives in the polymer matrix on the electrolyte-anode interface remains unclear. Here, solid electrolyte was studied for batteries with sodium metal anode based on polyethylene oxide (PEO) polymeric matrix containing ceramic additive. Extensive electrochemical analyses under both AC and DC conditions were performed, and chemical reactions between sodium metal and the PEO matrix, which produce interphases at the electrode-electrolyte interface, were investigated. Addition of sodium beta aluminate in the matrix appears to mitigate these reactions, removing a major obstacle on the way to effective all-solid-state rechargeable sodium batteries. [ABSTRACT FROM AUTHOR]

While electrospinning is an effective method for fabricating nanofibers with good application prospects, controlling the length of stable section of electrospinning jet is critical and remains challenging· In the paper, the effects of electrospinning parameters on the length of stable section have been investigated experimentally using polyacrylonitrile (PAN)· The results based on single factor experiments and orthogonal experiments showed that the stable-jet length increased with the increase of solution concentration, receiving distance, voltage and solution flow rate, and decreased with the enhanced concentration of salt which was commonly utilized as additive to facilitate the spinning. Furthermore, experimental results based on polyethylene oxide (PEO) and polyvinyl alcohol (PVA) showed that the length of stable section changed with increasing salt concentration, and due to the parametric interaction, the change was distinct under different driving voltages or solution concentration conditions. [ABSTRACT FROM AUTHOR]

Techniques for harvest and delivery of cell sheets have been improving for decades. However, cell sheets with complicated patterns closely related to natural tissue architecture were hardly achieved. Here, we developed an efficient method to culture and harvest cell sheets with complex shape (noted as microtissues) using temperature-responsive hydrogel consisting of expandable polyethylene oxide polymer at low temperature. Firstly, a temperature-responsive hydrogel surface with honeycomb patterns (50 and 100 µm in width) were developed through microcontact printing of polydopamine (PD). The human dermal fibroblasts (HDFBs) and human umbilical vein endothelial cells (HUVECs) spontaneously formed honeycomb-shaped microtissues on the patterned hydrogel surface. The microtissues on the hydrogel were able to be harvested and directly delivered to the desired target through thermal expansion of the hydrogel at 4 °C with an efficiency close to 80% within 10 min which is faster than conventional method based on poly(N-isopropylacrylamide). The microtissues maintained their original honeycomb network and intact structures. Honeycomb-patterned cell sheets also were fabricated through serial seeding of various cell lines, including HDFBs, HUVECs, and human adipose-derived stem cells, in which cells were attached along the honeycomb pattern. The underlying honeycomb patterns in the cell sheets were successfully maintained for 3 days, even after delivery. In addition, patterned cell sheets were successfully delivered in vivo while maintaining an intact structure for 7 days. Together, our findings demonstrate that micropatterned temperature-responsive hydrogel is an efficient method of one-step culturing and delivery of complex microtissues and should prove useful in various tissue engineering applications. Scaffold-free cell delivery techniques, including cell sheet engineering, have been developed for decades. However, there is limited research regarding culture and delivery of microtissues with complex architecture mimicking natural tissue. Herein, we developed a micro-patterned hydrogel platform for the culture and delivery of honeycomb-shaped microtissues. Honeycomb patterns were chemically engineered on the temperature-responsive hydrogel through microcontact printing of polydopamine to selectively allow for human dermal fibroblast or human umbilical vein endothelial cell adhesion. They spontaneously formed honeycomb-shaped microtissues within 24 hr upon cell seeding and directly delivered to various target area including in vivo via thermal expansion of the hydrogel at 4 °C, suggesting that the micro-patterned hydrogel can be an efficient tool for culture and delivery of complex microtissue. [Display omitted] [ABSTRACT FROM AUTHOR]

This study reexamines past studies of how drag-reducing polymer solutions modify the log-region of a developing turbulent boundary layer (TBL). The classical view was that the polymers modify the intercept constant without impacting the von Kármán coefficient, which results in the log-region being unaltered though shifted outward from the wall. However, recent work has shown this to be not accurate, especially at high drag reduction (HDR) (>40%). While the deviations to the von Kármán coefficient were conjectured to be related to polymeric properties, this had not been explored. This work examines the scatter in both log-region parameters and estimates the local polymeric properties. This shows that the scatter of the von Kármán coefficient between studies is related to the inner variable based Weissenberg number. In addition, recent polymer ocean results are included that support the implicit assumption in past studies that the maximum wall concentration should be used to define the local polymeric properties. [ABSTRACT FROM AUTHOR]

Basic understanding of surface reactions on the Li ion battery electrodes is of great importance as the interphase layers formed on the electrode surface due to the decomposition of electrolyte, during the initial battery cycles affects the safety, cycling life and performance of lithium-ion batteries. The effects of time, potential and cycling rate on the formation of cathode electrolyte interphases (CEIs) have been investigated on a V2O5 intercalation cathode by X-ray photoelectron spectroscopy (XPS). CEI layer on V2O5 based cathode is mainly composed of Li-alkyl carbonates (ROCO2Li), Li2CO3, LiF and some C−O, C=O species such as polyethylene oxide type compounds, Li-alkoxides (R−CH2OLi) and oxalates. Formation of CEI on cathode takes place during the discharge cycle while a partial dissolution/removal has been observed in the charging cycle. Removal of CEI species during the charging cycle could be ascribed to the puckering of V2O5 layers due to de-lithiation process. The formation and dissolution of LiF, ROCO2Li and other species has been observed until ≈215 ± 10 h, this may indicate that the decomposition of electrolyte is taking place till several cycles, which is an undesirable phenomenon in LIBs. CEI formation has shown a dependence on lower discharge potential, time and cycling rate. [ABSTRACT FROM AUTHOR]

In this study, the possibility to characterize the electrochemical characteristics of the particle-polymer interface in dual-phase electrolytes by measuring the contact potential difference with high local resolution is demonstrated. Two different polymer electrolytes, polyethylene oxide (PEO) and poly[bis-2-(2-methoxyethoxy)-ethoxyphosphazene] (MEEP), were investigated in combination with lithium ion conductive Li7La3Zr2O12 (LLZ) particles and two different mixed ionic-electronic conductive ceramic particles: uncoated and carbon coated LiFePO4 (LFP) as typical cathode material and uncoated Li4Ti5O12 as typical anode material. A distinct Volta potential gradient between the particles and the polymer was observable in all cases, except when no lithium salt was present within the polymer matrix. The measured potential gradients can be explained in terms of a contact potential between the polymer electrolyte and the ceramic electrolyte. A more negatively charged space charge layer around LFP particles in PEO matrix and around LLZ particles in MEEP can be explained by enrichment of salt anions in direct vicinity of the particle. Electrochemical characterization with impedance spectroscopy showed an increased conductivity for addition of LFP for PEO while the addition of various particles in different concentrations showed no effect on the conductivity of MEEP. The lithium transference number was unaffected by particle addition for all samples. [ABSTRACT FROM AUTHOR]

Tissue-engineered replacement discs are an area of intense investigation for the treatment of end-stage intervertebral disc (IVD) degeneration. These living implants can integrate into the IVD space and recapitulate native motion segment function. We recently developed a multiphasic tissue-engineered disc-like angle-ply structure (DAPS) that models the micro-architectural and functional features of native tissue. While these implants resulted in functional restoration of the motion segment in rat and caprine models, we also noted deficiencies in cell infiltration and homogeneity of matrix deposition in the electrospun poly(ε-caprolactone) outer region (annulus fibrosus, AF) of the DAPS. To address this limitation, here, we incorporated a sacrificial water-soluble polymer, polyethylene oxide (PEO), as a second fiber fraction within the AF region to increase porosity of the implant. Maturation of these PEO-modified DAPS were evaluated after 5 and 10 weeks of in vitro culture in terms of AF biochemical content, MRI T2 values, overall construct mechanical properties, AF micromechanical properties and cell and matrix distribution. To assess the performance of the PEO-modified DAPS in vivo , precultured constructs were implanted into the rat caudal IVD space for 10 weeks. Results showed that matrix distribution was more homogenous in PCL/PEO DAPS, as evidenced by more robust histological staining, organized collagen deposition and micromechanical properties, compared to standard PCL-only DAPS in vitro. Cell and matrix infiltration were also improved in vivo , but no differences in macromechanical properties and a trend towards improved micromechanical properties were observed. These findings demonstrate that the inclusion of a sacrificial PEO fiber fraction in the DAPS AF region improves cellular colonization, matrix elaboration, and in vitro and in vivo function of an engineered IVD implant. This work establishes a method for improving cell infiltration and matrix distribution within tissue-engineered dense fibrous scaffolds for intervertebral disc replacement. Tissue-engineered whole disc replacements are an attractive alternative to the current gold standard (mechanical disc arthroplasty or vertebral fusion) for the clinical treatment of patients with advanced disc degeneration. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The high areal-energy and power requirements of advanced microelectronic devices favor the choice of a lithium-ion system, since it provides the highest energy density of available battery technologies suitable for a variety of applications. Several attempts have been made to produce primary and secondary thin-film batteries utilizing printing techniques. These technologies are still at an early stage, and most currently-printed batteries exploit printed electrodes sandwiching self-standing commercial polymer membranes, produced by conventional extrusion or papermaking techniques, followed by soaking in non-aqueous liquid electrolytes. In this work, we suggest a novel flexible-battery design and report the initial results of development and characterization of novel 3D printed allsolid-state electrolytes prepared by fused-filament fabrication (FFF). The electrolytes are composed of LiTFSI, polyethylene oxide (PEO), which is a known lithium-ion conductor, and polylactic acid (PLA) for enhanced mechanical properties and high-temperature durability. The 3D printed electrolytes were characterized by means of ESEM imaging, mass spectroscopy, differential scanning calorimetry (DSC) and electrochemical impedance spectroscopy (EIS). TOFSIMS analysis reveals formation of lithium complexes with both polymers. The flexible all-solid LiTFSI-based electrolyte exhibited bulk ionic conductivity of 3 × 10-5 S/cm at 90°C and 156ohmxcm² resistance of the solid electrolyte interphase (SEI). We believe that the coordination mechanism of the lithium cation by the oxygen of the PLA chain is similar to that of PEO and local relaxation motions of PLA chain segments could promote Li-ion hopping between oxygens of adjacent CH-O groups. What is meant by this is that PLA not only improves the mechanical properties of PEO, but also serves as a Li-ion-conducting medium. These results pave the way for a fully printed solid battery, which enables free-form-factor flexible geometries. [ABSTRACT FROM AUTHOR]

With the rapid development of high-power and high-energy density lithium-ion batteries, thermal safety has become a critical issue. Due to the fast microstructure change triggered by heat, thermosensitive polymers have aroused increasing attention as thermal shutdown material candidates to prevent the thermal runaway of lithium-ion batteries. In this work, a sandwich-structured polyacrylonitrile/polyethylene oxide/polyacrylonitrile (PAN/PEO/PAN) fibrous membrane with prompt thermal shutdown properties and high thermal stability is prepared using electrospinning technique. The inner layer of the fusible PEO fibrous membrane impart the composite separator with a prompt thermal shutdown function at 80 °C. Meanwhile, the outer layer of the heat-resistant PAN membrane remains thermally stable, even at 200 °C. The large buffering temperature difference (120 °C) between the thermal shutdown temperature and the thermally stable temperature of the composite separator is wider than most of the reported separators and effectively enhances the thermal safety of the lithium-ion batteries. In addition, the PAN/PEO/PAN separator exhibits a higher porosity, better electrolyte wettability, larger ionic conductivity, and lower interfacial resistance compared with a commercial polypropylene/polyethylene/polypropylene (PP/PE/PP) separator. Moreover, the coin cells assembled by the PAN/PEO/PAN separator presents stable cycle performance and excellent rate capability. Therefore, the novel PAN/PEO/PAN membrane shows great potential as a promising candidate for much safer lithium-ion battery separators. [ABSTRACT FROM AUTHOR]

Recent literature shows a great controversy on the lithium transference number in salt-in-polymer electrolytes, namely Libis(trifluoromethanesulfonyl)amide (LiTFSA) in polyethylene oxide (PEO), as different experimental methods and theories yield strongly contradictory results [I. Villaluenga, D. M. Pesko, K. Timachova, Z. Feng, J. Newman, V. Srinivasan and N. P. Balsara, J. Electrochem. Soc., 165, A2766 (2018) and K. Pozyczka, M. Marzantowicz, J. R. Dygas and F. Krok, Electrochim. Acta, 227, 127 (2017)]. Here, we introduce the method of electrophoretic NMR (eNMR) as a model-free approach to shed light on the controversy. Electrophoretic mobilities of the ions in PEO/LiTFSA electrolytes of varying salt concentration are measured in order to directly obtain lithium transference numbers. At the field strengths involved, the mobilities depend on the electric field, due to nonlinear effects which can be cancelled out by an extrapolation to the low field regime. In all cases, the drift direction of lithium is opposite to the TFSA anion and a high effective charge of both ions (> 0.7) indicates mostly uncorrelated ion movement. The resulting lithium transference numbers are around 0.2 and are almost independent on salt concentration. They thus confirm the literature results from Bruce-Vincent methods, but not those from a Newman approach. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We compare two experimental approaches for measuring the cation transference number in mixtures of polyethylene oxide (PEO) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt: the well-established current-interrupt method proposed by Ma et al. [J. Electrochem. Soc., 142, 1859 (1995)], and a more recent method based on measuring the steady-state current proposed by Balsara and Newman [J. Electrochem. Soc., 162, A2720 (2015)]. In electrolytes comprised of high molecular weight PEO, the data from the two techniques agree, highlighting the equivalence of these two approaches. However, in lower molecular weight PEO electrolytes the values of the two approaches diverge at low salt concentrations. We posit this is because the approach of Ma et al. requires measurements that are sensitive to the nature of the interface between the electrolyte and the electrode. The transference numbers measured by the approach of Balsara and Newman for both low and high molecular weight samples vary from 0.7 to -0.8 and are within experimental error throughout the entire salt concentration window. [ABSTRACT FROM AUTHOR]

Abstract In light of current concerns about environmental impact, ionic liquids have been tested in a number of industrial applications, including gas purification, lubrication, and catalysis. In this work, cost-effective alkylammonium-based protic ionic liquids (PIL) were utilized as high-dosage gas hydrate inhibitors in order to achieve an inexpensive feedstock. Three structurally different PILs, ethylammonium formate ([EA][Of]), dimethylammonium formate ([DMA][Of]), and dimethylethylammonium formate ([DMEA][Of]), were studied to determine their inhibitory effect on methane gas hydrates. All of the studied PILs were initially tested for thermodynamic gas hydrate inhibition at 5 wt% and at 10 wt% to understand the effect of concentration by increasing the dosage. These PILs were produced by adding primary, secondary, and tertiary amines to formic acid, which is mildly acidic in nature and has biological significance. The PILs showed similar thermodynamic hydrate inhibition (THI) effects at the studied concentrations. The THI trend ([EA][Of] ≥ [DMA][Of] ≥ [DMEA][Of]) reflects the small effect of the structural variation of the cation, with the common formate anion providing the dominant inhibitory action due to presence of a carboxylic group. The pressure-temperature (P-T) equilibrium curve data of the investigated PILs were compared with the existing literature data for ILs including [TBMA][Of] at 10 wt% and 5 wt%. The comparison plots reveal that the THI effects of the studied PILs are better than or comparable to the other ILs, which is the matter of discussion over cost effective operation. Additionally, experimental kinetic hydrate inhibition (KHI) data were collected for 5 wt% PIL systems using polyethylene oxide (1 wt%) as an additive to demonstrate its synergistic effect. Graphical abstract Image 1 Highlights • Cost effective alkylammonium-based protic ionic liquids (PIL) were utilized as high-dosage gas hydrate inhibitors. • PILs exhibited thermodynamic hydrate inhibition (THI) effect at studied concentrations. • Selected ILs exhibited dual-functional behavior as THI and KHI. [ABSTRACT FROM AUTHOR]

Composite polyethylene-oxide/garnet electrolytes containing LiTFSI as the lithium salt have a Li + conductivity σ Li > 10 −4 S cm −1 at 55 °C and a low plating/stripping impedance of a dendrite-free Li-metal anode; they have been developed for a safe solid-state Li-metal rechargeable battery. Composites consisting of “ceramic-in-polymer” to “polymer-in-ceramic” that are flexible and mechanically robust are fabricated by hot-pressing. Safe pouch cells with a remarkable flexibility have been fabricated. Solid-state LiFePO 4 | Li batteries with electrolytes of “ceramic-in-polymer” and “polymer-in-ceramic” deliver excellent cycling stability with high discharge capacities (139.1 mAh g –1 with capacity retention of 93.6% after 100 cycles) and high capacity retention (103.6% with coulombic efficiency of 100% after 50 cycles) at 0.2 C and 55 °C. Both kinds of electrolytes can be applied to solid-state lithium batteries. [ABSTRACT FROM AUTHOR]

Biological activity dressings on wound healing consist of Prionace glauca cartilage type II collagen (CII) cartilage, chitosan and polyethylene oxide (PEO). The dressing fibers are successfully obtained by electrospinning from the acetic acid aqueous solution (80 %, volume fraction). An effective quadric polynomial regression model, including the feed speed (mL/h) , the applied voltage (kV) and the nozzle-collector distance (cm), was set up by response surface methodology. By using the optimized process parameters (applied voltage 20 kV, nozzle-collector distance 16.6 cm and feed speed 0.70 mL/h) , the mean diameter (230.34 nm) was reduced by about 10 % compared with the original one. [ABSTRACT FROM AUTHOR]

Camptothecin (CPT)-containing promicelle polymers (PM CPT ) based on 4-armed poly(ethylene glycol) (PEG) were developed previously to self-assemble into folate-targeted and glutathione (GSH)-sensitive micelles (M CPT ). To address severe systemic toxicity and lack of tumor specificity implicated in the intravenous administration of M CPT , a micelle-generating depot has been developed by blend electrospinning of PEG-poly(lactide) (PELA) copolymers, PM CPT and polyethylene oxide (PEO). Upon implantation of the depot onto a tumor, PM CPT are sustainably released to self-assemble into M CPT on the tumor site. The release of PM CPT is adjusted by varying PEO/PELA ratios and reaches in the range of 23–92% after 30 days of incubation. By making use of the aggregation-induced emission (AIE) features of tetraphenylethylene (TPE) derivatives, the release process of TPE-containing promicelle polymers (PM TPE ) from the depot and the spontaneous formation of micelles (M TPE ) have been monitored from the self-assembly-induced fluorescence light-up both in vitro and in vivo . Compared with intravenous injection of M CPT , the micelle-generating depot has significantly enhanced micelle accumulation in the tumor for an extended period of time and resulted in stronger tumor inhibitory efficacy, reduced systemic toxicity and more effective inhibition of tumor metastasis, demonstrating great potential for targeted cancer therapy with sustained efficacy. Statement of significance The promicelle polymer-co-electrospun fibers are developed to form a micelle-generating depot after implantation onto the tumor. The promicelle polymers are continuously released and simultaneously self-assemble into folate-targeted and glutathione-sensitive micelles, ensuring sustained micelle delivery for more than 30 days. The process of micelle formation in the tumor tissue is visualized in vivo for the first time based on the mechanism of aggregation-induced emission. This in situ micelle formation also prevents premature drug release and rapid clearance from the bloodstream. In addition, these fibers deliver anti-cancer agents directly within tumor cells via dual selectivity ( i.e. spatially selective accumulation in tumor tissues via implantation and selective internalization into tumor cells via folate receptor-mediated endocytosis) and on-demand drug release in response to cytosol GSH. They exhibit superior tumor inhibitory efficacy with minimal systemic toxicity, and prevent from malignant metastasis of cancer cells. [ABSTRACT FROM AUTHOR]

Polymer electrolytes (PEs) have attracted much attention due to their numerous applications such as rechargeable batteries, sensors, electro chromic devices, super capacitors, etc. A series of poly(ethylene oxide) (PEO) and sodium iodide (NaI) based PEs were prepared with different concentrations, hereafter referred to as the number of oxygen atoms (n) to a sodium (n:1). In this study samples with n = 7.5,10,15,20,30,40,50,60 and 80 were prepared. In this study, PEO was used as the polymer. Acetonitrile, sodium iodide was used as solvent and salt, respectively. Free standing films of polymer electrolytes were prepared using solvent casting method. Samples were characterized by different experimental techniques like complex impedance spectroscopy, DC conductivity, polarized light microscopy and Differential Scanning Calorimetry (DSC). The dependence of salt concentration on ionic conductivity of PEO-NaI PEs was investigated using complex impedance spectroscopy whereas the changes in the spherulite formation of PEs, was observed using Polarized light microscopy. DC polarization test was used to calculate ionic transference numbers. The melting temperature and melting enthalpy were studied using DSC. The ionic conductivity increased with increasing salt concentration and the sample temperature. The amorphous nature was increased with the increasing salt concentration. This is evident from the slight reduction in the onset and the maximum temperature of the pure PEO melting peaks in samples with high salt concentrations. This is supported by the images of spherulites obtained using the polarized light microscope. Fourier Transform Infrared (FTIR) spectroscopy studies show the cation polymer interactions an important concept in ionic transport mechanism. [ABSTRACT FROM AUTHOR]

Interface stability between cathode and electrolyte is closely related to the interface resistance and electrochemical performance of all-solid-state lithium ion batteries (LIBs). However, the significant interface issues between cathode and all-solid-state polymer electrolyte have been researched rarely. Here, we demonstrate that severe interface decomposition reactions occur continually and deteriorate the cycling life of high voltage LiCoO2/cellulose-supported poly(ethylene oxide) (PEO)-lithium difluoro(oxalato)borate (LiDFOB)/Li battery between 2.5 and 4.45 V vs. Li/Li+. To improve the interface stability between LiCoO2 and PEO-LiDFOB electrolyte, we modify the LiCoO2 surface by a thin layer of high ionic conducting and electrochemical oxidation resistant poly(ethyl cyanoacrylate) (PECA) through in-situ polymerization method. The PECA coating layer significantly suppresses the continuous decomposition of lithium difluoro(oxalato)borate (LiDFOB) salt in PEO electrolyte. As a result, the PECA-coated LiCoO2/PEO-LiDFOB/Li battery shows decreased interface resistance and enhanced cycling stability. This work will enlighten the understanding of interface stability and enrich the modification strategy between cathode and polymer electrolyte as well as boost the further development of all-solid-state LIBs. [ABSTRACT FROM AUTHOR]

• Green PVDF/PEO hollow fiber composite membrane was fabricated by TIPS method based on concentric circle spinning process. • The addition of PEO changed the phase separation rate and effectively regulated the pore structure. • Compared with PVDF hollow fiber membrane, the mechanical strength of the braided tube enhanced PVDF hollow fiber membrane was significantly improved. Currently, membrane separation technology was used in the fields of water treatment, gas separation and electrodialysis. Among them, water treatment was still the main field of application of membrane separation technology, for example, in the treatment of industrial wastewater, membrane separation technology does not destroy or change the composition of wastewater during the treatment process, and valuable products can be recovered and used commercially. The braided tube reinforced polyvinylidene fluoride (PVDF) hollow fiber composite membranes were successfully prepared by thermally induced phase separation (TIPS) method with no harmful diluent and additives (green preparation) based on concentric circle spinning process. The membrane morphology was characterized by scanning electron microscopy (SEM) and confocal scanning microscopy (CSM). The effects of polyethylene oxide (PEO) content on the performance of the prepared hollow fiber membranes were investigated in terms of mechanical strength, pure water flux and bovine serum protein (BSA) rejection. The results showed that the addition of PEO promoted the phase separation process and inhibited the growth of PVDF spherical crystals. When the PEO content was 15wt%, the membrane has high pure water flux and excellent BSA rejection. In addition, the tensile strength of the reinforced hollow fiber membranes exceeded 100 MPa and exhibited favorable interfacial bonding. [Display omitted] [ABSTRACT FROM AUTHOR]

Food-friendly packaging are supposed to keep the food quality and freshness in terms of moisture and odour and protect foods against microbial putrefying contaminants and oxidant agents. This study has aimed to fabricate biodegradable electrospun chitosan/polyethylene oxide membranes loaded with gallic acid and nisin for antioxidant/antibacterial properties. gallic acid/nisin loaded core-shell chitosan/polyethylene oxide nanofiberous membranes were fabricated through electrospinning and characterized by transmission and scanning electron microscopy, fourier-transform infrared spectroscopy, and differential scanning calorimetry as well as antioxidant and antibacterial activities. gallic acid (10%)/nisin (0.05% and 0.07%) loaded membranes showed maximal tensile strength as well as antioxidant and antimicrobial effects for 20 and 60 days, respectively. Stretchable electrospun gallic acid/nisin loaded chitosan/polyethylene oxide membranes possess antioxidant and antibacterial properties and can be suggested as potential food packaging membranes. [Display omitted] • Gallic acid and Nisin loaded chitosan/PEO membranes were fabricated through electrospinning. • GA/Nisin loaded membranes are stretchable. • GA/Nisin loaded membranes possess antioxidant/antimicrobial properties. [ABSTRACT FROM AUTHOR]

The performance of battery electrolytes depends on three independent transport properties: ionic conductivity, diffusion coefficient, and transference number. While rigorous experimental techniques for measuring conductivity and diffusion coefficients are well-established, popular techniques for measuring the transference number rely on the assumption of ideal solutions. We employ three independent techniques for measuring transference number, t+, in mixtures of polyethylene oxide (PEO) and lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) salt. Transference numbers obtained using the steady-state current method pioneered by Bruce and Vincent, t+,SS, and those obtained by pulsed-field gradient NMR, t+,NMR, are compared against a new approach detailed by Newman and coworkers, t+,Ne, for a range of salt concentrations. The latter approach is rigorous and based on concentrated solution theory, while the other two approaches only yield the true transference number in ideal solutions. Not surprisingly, we find that t+,SS and t+,NMR are positive throughout the entire salt concentration range, and decrease monotonically with increasing salt concentration. In contrast, t+,Ne has a non-monotonic dependence on salt concentration and is negative in the highly-concentrated regime. Our work implies that ion transport in PEO/LiTFSI electrolytes at high salt concentrations is dominated by the transport of ionic clusters. [ABSTRACT FROM AUTHOR]

• The non-uniform diffusion of PIP led to the formation of Turing structure. • TFC membrane has greater surface roughness and lower thickness of the PA layer. • Attachment of quaternary ammonium salt reduced the surface electronegativity. • The hydration layer of PEO enhances the fouling resistance of the membrane. The speed of the interfacial polymerization reaction is considered to be the decisive factor for the thickness and surface morphology of the polyamide layer. The reaction rate can be controlled by controlling the diffusion rate of the aqueous monomer. Here, firstly, polyethylene oxide was added into the aqueous solution to increase the viscosity of the aqueous phase to reduce the reaction rate. Then choline chloride (CC) was grafted on the surface of the nascent polyamide membrane by a surface grafting method for secondary modification. A polyamide nanofiltration membrane with a special Turing structure was prepared on the surface of polyethersulfone support membrane. The desalination performance of composite membrane was investigated. The results showed that the addition of PEO resulted in the regular Turing structure on the surface of the composite membrane. When the addition amount reached 1%, the performance of the composite membrane was the best. After the secondary modification of CC, the rejection rate of Na 2 SO 4 was more than 96%, and the permeation flux could reach 125.9 L/(m2·h·MPa). It is expected to be applied in the fields of seawater desalination and sewage purification. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study modifying compounds on the basis of interpolymer complexes (IPC) of polyacrylic acid with nonionic polymers (polyvinyl alcohol, polyethylene oxide, polyacrylamide) were obtained. The conditions for formation of polymer-polymer complexes in aqueous media were studied. The method of impregnation of cotton blended fabrics with different surface mass of compositions based on interpolymer complexes of stoichiometric and non-stoichiometric composition is presented. The possibility of adjusting the gain of IPC in tissue structure was also determined. The impact of IPC was proved to increase the oxygen index of tissues, reducing their flammability, with an almost complete reduction of the self-combustion time. [ABSTRACT FROM AUTHOR]

Although poly(glycerol sebacate) (PGS) has enjoyed great success in soft tissue engineering, it remains challenging to fabricate PGS fibers. In this study, coaxial electrospinning, in which polylactide (PLA) was used to confine and draw PGS prepolymer, was used to fabricate PGS fibrous membranes. Specifically, effects of adding poly(ethylene oxide) (PEO), which was removed prior to curing, in the shell were investigated. Transmission and scanning electron microscopy were used to confirm core–shell structure and morphology of fibers, respectively. Both the removal of PEO or PLA in the shell and the efficacy of PGS curing were verified by Fourier transform infrared spectroscopy and differential scanning calorimetry. Mechanical properties of the membranes with different shell and core contents were examined. We found that the addition of PEO to the shell reduced Young׳s modulus of the resulting cured membrane and increased its elongation at break significantly, the latter indicating better PGS curing. Moreover, with the addition of PEO, increasing PGS prepolymer concentration further increased the elongation at break and appeared to enhance the structural integrity of fibers; PGS fibrous membranes (with no PLA shell) were thus successfully fabricated after the removal of PLA. The Young׳s modulus of the PGS fibrous membrane was ~0.47 MPa, which is similar to that of PGS solid sheets and some soft tissues. Finally, the cytocompatibility of the electrospun membranes was validated by Alamar blue and LDH assays. [ABSTRACT FROM AUTHOR]

Acrylates have been widely used in the synthesis of pharmaceutical polymers. The quantitation of residual acrylate monomers is vital as they are strong irritants and allergens, but after polymerization, are relatively inert, causing no irritation and allergies. Poly(ethylene oxide) (PEO) hydrogels were prepared using pentaerythritol tetra-acrylate (PETRA) as UV crosslinking agent. A simple, accurate, and robust quantitation method was developed based on gas chromatographic techniques (GC), which is suitable for routine analysis of residual PETRA monomers in these hydrogels. Unreacted PETRA was initially identified using gas chromatography–mass spectrometry (GC–MS). The quantitation of analyte was performed and validated using gas chromatography equipped with a flame ionization detector (GC–FID). A linear relationship was obtained over the range of 0.0002%–0.0450% (m/m) with a correlation coefficient ( r 2 ) greater than 0.99. The recovery (>90%), intra-day precision (%RSD <0.67), inter-day precision (%RSD <2.5%), and robustness (%RSD <1.62%) of the method were within the acceptable values. The limit of detection (LOD) and limit of quantitation (LOQ) were 0.0001% (m/m) and 0.0002% (m/m), respectively. This assay provides a simple and quick way of screening for residual acrylate monomer in hydrogels. [ABSTRACT FROM AUTHOR]

In contrast to modification with conventional PEO-silanes (i.e. no siloxane tether), silicones with dramatically enhanced protein resistance have been previously achieved via bulk-modification with poly(ethylene oxide) (PEO)-silane amphiphiles α-(EtO) 3 Si(CH 2 ) 2 -oligodimethylsiloxane 13 - block -PEO n -OCH 3 when n = 8 and 16 but not when n = 3. In this work, their efficacy was evaluated in terms of optimal PEO-segment length and minimum concentration required in silicone. For each PEO-silane amphiphile ( n = 3, 8, and 16), five concentrations (5, 10, 25, 50, and 100 μmol per 1 g silicone) were evaluated. Efficacy was quantified in terms of the modified silicones’ abilities to undergo rapid, water-driven surface restructuring to form hydrophilic surfaces as well as resistance to fibrinogen adsorption. Only n = 8 and 16 were effective, with a lower minimum concentration in silicone required for n = 8 (10 μmol per 1 g silicone) versus n = 16 (25 μmol per 1 g silicone). Statement of Significance Silicone is commonly used for implantable medical devices, but its hydrophobic surface promotes protein adsorption which leads to thrombosis and infection. Typical methods to incorporate poly(ethylene oxide) (PEO) into silicones have not been effective due to the poor migration of PEO to the surface-biological interface. In this work, PEO-silane amphiphiles – comprised of a siloxane tether ( m = 13) and variable PEO segment lengths ( n = 3, 8, 16) – were blended into silicone to improve its protein resistance. The efficacy of the amphiphiles was determined to be dependent on PEO length. With the intermediate PEO length ( n = 8), water-driven surface restructuring and resulting protein resistance was achieved with a concentration of only 1.7 wt%. [ABSTRACT FROM AUTHOR]

A lithium stable, lithium-ion conducting solid electrolyte, Li1.4Al0.4Ge0.2Ti1.4(PO4)3 (LAGTP), was developed by protecting the surface with a polyethylene oxide (PEO) based polymer electrolyte. A surface of tape-cast LAGTP film with epoxy resin was coated with a PEO8Li(FSO3)2N-tetraethylene glycol dimethyl ether (G4)-10 wt% BaTiO3 composite polymer electrolyte. The electrical conductivity of the LAGTP film with a 4 wt% polymer electrolyte was 1.06 × 10-4 S·cm-1 at 25°C and 5.92 × 10-4 S·cm-1 at 60°C. A cell consisting of Li/4 wt% (PEO-G4-10 wt% BaTiO3)-coated LAGTP/4 M Li(CF3SO2) 2N in dimethoxyethane/Li exhibited a steady cell resistance of 600 Ω. cm2 at 25°C for 4 months. The stable and low interface resistance confirms that the thin PEO-based layer succeeded in preventing the reduction from Ti4+/Ge4+ to Ti3+/Ge3+ in LAGTP by lithium. No lithium dendrite formation was observed at the interface of the surface-coated LAGTP and lithium at 1.0 mA. cm-2 and 25°C for 40 h lithium deposition. [ABSTRACT FROM AUTHOR]

Flexible and rigid long chain polymers in very dilute solutions can significantly reduce the drag in turbulent flows. The polymers successively stretch and coil by interacting with the turbulent structures, which changes the turbulent flow and further imposes a transient behavior on the drag reduction (DR) as well as a subsequent mechanical polymer degradation. This time-dependent phenomenon is strongly affected by a number of parameters, which are analyzed here, such as the Reynolds number, polymer concentration, polymer molecular weight, and salt concentration. This last parameter can dramatically modify the polymeric structure. The investigation of the salt concentration s impact on the DR is mostly motivated by some potential applications of this technique to ocean transport and saline fluid flows. In the present paper, a cylindrical double gap rheometer device is used to study the effects of salt concentration on DR over time. The reduction of drag is induced by three polymers: poly (ethylene oxide) (PEO), polyaaylamide (PAM), and xanthan gum (XG). These polymers are dissolved in deionized water both in the presence of salt and in its absence. The DR is displayed from the vety start of the test to the time when the DR achieves its final level of efficiency, following the mechanical degradations. The presence of salt in PEO and XG solutions reduces the maximum DR, DRmax, as well as the time to achieve it. In contrast, the DR does not significantly change over the time for PAM solutions upon the addition of salt. [ABSTRACT FROM AUTHOR]

There is a demand for materials to replace or augment the use of sutures and staples in surgical procedures. Currently available commercial surgical adhesives provide either high bond strength with biological toxicity or polymer and protein-based products that are biologically acceptable (though with potential sensitizing potential) but have much reduced bond strength. It is desirable to provide novel biocompatible and biodegradable surgical adhesives/sealants capable of high strength with minimal immune or inflammatory response. In this work, we report the end group derivatization of 8-arm star PEOs with aldehyde and amine end groups. Gels were prepared employing the Schiff-base chemistry between the aldehydes and the amines. Gel setting times, swelling behavior and rheological characterization were carried out for these gels. The mechanical-viscoelastic properties were found to be directly proportional to the crosslinking density of the gels, the 10K PEO gel was stiffer in comparison to the 20K PEO gel. The adhesive properties of these gels were tested using porcine skin and showed excellent adhesion properties. Cytotoxicity studies were carried out for the individual gel components using two different methods: (a) Crystal Violet Staining assay (CVS assay) and (b) impedance and cell index measurement by the xCELLigence system at concentrations >5%. Gels prepared by mixing 20% w/w solutions were also tested for cytotoxicity. The results revealed that the individual gel components as well as the prepared gels and their leachables were non-cytotoxic at these concentrations. Statement of Significance This work presents a new type of glue that is aimed at surgery applications using a water soluble star shaped polymer. It show excellent adhesion to skin and is tough and easy to use. We show that it is very biocompatible based on tests on live human cells, and could therefore in principle be used for internal surgery. Comparison with other reported and commercial glues shows that it is stronger than most, and does not swell in water to the same degree as many other water based bioadhesives. [ABSTRACT FROM AUTHOR]

Drug-coated balloons (DCBs) are used to treat various cardiovascular diseases. Currently available DCBs carry drug on the balloon surface either solely or using different carriers. Several studies have shown that a significant amount of drug is lost in the blood stream during balloon tracking to deliver only a sub-therapeutic level of drug at the treatment site. This research is focused on developing paclitaxel (PAT) loaded polyethylene oxide (PEO) films (PAT–PEO) as a controlled drug delivery carrier for DCBs. An array of PAT–PEO films were developed in this study to provide tailored release of >90% of drug only at specific time intervals, which is the time frame required for carrying out balloon-based therapy. The characterizations of PAT–PEO films using SEM, FTIR, and DSC showed that the films developed were homogenous and the PAT was molecularly dispersed in the PEO matrix. Mechanical tests showed that most PAT–PEO films developed were flexible and ductile, with yield and tensile strengths not affected after PAT incorporation. The viability, proliferation, morphology, and phenotype of smooth muscle cells (SMCs) interacted with control-PEO and PAT–PEO films were investigated. All control-PEO and PAT–PEO films showed a significant inhibitory effect on the growth of SMCs, with the degree of inhibition strongly dependent on the w/v% of the polymer used. The PAT–PEO coating was produced on the balloons. The integrity of PAT–PEO coating was well maintained without any mechanical defects occurring during balloon inflation or deflation. The drug release studies showed that only 15% of the total PAT loaded was released from the balloons within the initial 1 min (typical balloon tracking time), whereas 80% of the PAT was released between 1 min and 4 min (typical balloon treatment time). Thus, this study demonstrated the use of PEO as an alternate drug delivery system for the balloons. Statement of Significance Atherosclerosis is primarily responsible for cardiovascular diseases (CVDs) in millions of patients every year. Drug-coated balloons (DCBs) are commonly used to treat various CVDs. However, in several currently used DCBs, a significant amount of drug is lost in the blood stream during balloon tracking to deliver only a sub-therapeutic level of drug at the treatment site. In this study, paclitaxel containing polyethylene oxide (PEO) films were developed to provide unique advantages including drug release profiles specifically tailored for balloon-based therapy, homogeneous films with molecularly dispersed drug, flexible and ductile films, and exhibits significant inhibitory effect on smooth muscle cell growth. Thus, this study demonstrated the use of PEO as an alternate drug delivery platform for DCBs to improve its efficacy. [ABSTRACT FROM AUTHOR]

We demonstrate a label-free and sheathless hydrodynamic approach that successfully separate particles and cells by size in straight microchannels. Particles and cells have size-dependent stable equilibrium positions in 0.1wt % polyethylene oxide (PEO, M w = 4×10 6 g/mol) solution in a rectangular microchannel: 1μm particles focus at the channel center while 3μm particles focus near the channel side walls, which is completely different from the previously observed focusing at the channel center regardless of particle size. The effect of blockage ratio accounts for the deviation of large particles from the center. Utilizing this size-dependent differential migration, we successfully separate E. coli bacteria and red blood cells (RBCs) with both components tightly focused at different equilibrium positions in a straight microchannel, which has good parallelizability for higher throughput. [ABSTRACT FROM AUTHOR]

We analyze the gas separation performance of five polyether-block-amide type copolymers (Pebax® 1657, Renew®, 2533, 3533 and 4533). These codes are composed of different hard and rubbery segments with different proportions. Dense membranes were prepared by the casting-solution method and studied by elemental, thermogravimetric and X-ray diffraction analyses, FTIR-ATR spectroscopy and single and mixed gas permeation. Codes with the best separation performance are those of polyethylene oxide as the soft phase (Pebax® 1657 and Renew®) due to the more intense interactions of this segment with CO 2 , which increases the CO 2 /N 2 solubility selectivity (17.5 and 30.5 for Pebax® 1657 and Renew®, respectively) and hence the CO 2 /N 2 separation selectivity of the membrane (36 and 37 for Pebax® 1657 and Renew®, respectively, obtained from mixed gas permeation). It is also noticeable that the proportion of the soft phase in the copolymer determines the permeability of CO 2. It was found that the codes with a greater soft/hard segment ratio (Pebax® 2533 and 3533) have also a greater permeability value (239 and 220 Barrer for Pebax® 2533 and 3533, respectively, measured by mixed gas permeation). Pebax® Renew® was the polymer with the best separation performance with CO 2 permeabilities of 167 and 164 Barrer and CO 2 /N 2 selectivities of 41 and 37, measured by single and mixed gas permeation, respectively. The comparison between the single and mixture gas permeation results revealed a relatively good correspondence between both for most of the Pebax® codes tuned by the solubility and diffusion properties of the polymers. [Display omitted] • The gas separation performance of five codes of Pebax® type copolymer was studied. • Results obtained by mixed gas and time lag experiments were compared for the CO 2 /N 2 system. • The nature and proportion of PA and PE determined the final membrane separation performance. • Apparent activation energies of permeation were calculated using both methods. [ABSTRACT FROM AUTHOR]

Geographical and temporal differences of microplastic occurrence were documented in water and fish collected in 2017 and 2019 from the Giglio Island (North Tyrrhenian Sea) close to the area where the Costa Concordia sank in January 2012. Results on water samples showed a site-dependent difference, suggesting the role of surface current dynamics in the microplastic local distribution, while tested Neuston nets (200 μm and 330 μm mesh size) did not influence microplastic retention efficiency. Fish exhibited in 2019 a higher frequency of specimens positive to microplastic ingestion with respect to 2017, with an occurrence higher than those typically observed in other Mediterranean areas. Both in water and fish, fragments were the dominating shape, polypropylene and polyethylene were the prevalent polymers, without particular difference between sites and years. This study highlights the importance of applying microplastic investigation in biotic and abiotic matrices for an effective monitoring of this pollution in the marine environment. • An integrated approach including both seawater and biota samples should be suggested for MPs monitoring. • The Neuston-net mesh size (200 or 330 μm) did not influence MPs retention efficiency. • High number of textile microfibers (MFs) is extracted from blank samples. • Both in water and fish samples, fragments were the dominating shape MPs. • Polypropylene and polyethylene were the most prevalent MPs polymers. [ABSTRACT FROM AUTHOR]

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The present work investigates the formulation and biopharmaceutical estimation of gastric floating drug delivery system (GFDDS) of propranolol HCl using semi-synthetic polymer carboxymethyl ethyl cellulose (CMEC) and a synthetic polymer polyethylene oxide (PEO). A central composite design was applied for optimization of polymer quantity (CMEC or PEO) and sodium bicarbonate concentration as independent variables. The dependent variables evaluated were: % of drug release at 1 hr (D1hr), % drug release at 3 hr (D3hr) and time taken for 95% of drug release (t95). Numerical optimization and graphical optimization were conducted to optimize the response variables. All observed responses of statistically optimized formulations were in high treaty with predicted values. Accelerated stability studies were conducted on the optimized formulations at 40±2°C/75% ±5% RH and confirm that formulations were stable. Optimized formulations were evaluated for in vivo buoyancy characterization in human volunteers and were found buoyant in gastric fluid. Gastric residence time was enhanced in the fed but not the fasted state. The optimized formulations and marketed formulation were administered to healthy human volunteers and evaluated for pharmacokinetic parameters. Mean residence time (MRT) was prolonged and AUC levels were increased for both optimized floating tablets when compared with marketed product. High relative bioavailability obtained with optimized gastric floating tablets compared to commercial formulation, indicated the improvement of bioavailability. [ABSTRACT FROM AUTHOR]

The solvent-free hybrid solid electrolytes composed of lithium aluminum germanium phosphate (LAGP) and polyethylene oxide) (PEO) were prepared in the form of flexible film, and their electrochemical characteristics were investigated. The addition of ion-conductive LAGP powder into PEO-based solid polymer electrolyte improved the electrical and mechanical properties of solid electrolytes. For the hybrid solid electrolytes examined in this study, the optimum composition of LAGP was found to be about 60~80 wt% in consideration of ionic conductivity, mechanical stability and formability for flexible thin film. The all solid-state Li/LiFePO4 cell assembled with hybrid solid electrolyte delivered an initial discharge capacity of 137.6 mAh g-1 and exhibited good cycling stability at 55°C. [ABSTRACT FROM AUTHOR]

Adsorption of proteins on surfaces placed in biological fluids is a ubiquitous and mostly irreversible phenomenon, desirable or not, but often uncontrolled. Adsorption of most proteins on poly(ethylene oxide) (PEO) brushes is very limited, while the amount of proteins adsorbed on poly(acrylic acid) (PAA) brushes varies with the pH and ionic strength ( I ) of the protein solution. Mixed brushes of PEO and PAA are designed here to reversibly adsorb and desorb albumin, lysozyme, collagen and immunoglobulin G, four very different proteins in terms of size, solubility and isoelectric point. Protein adsorption and desorption are monitored using X-ray photoelectron spectroscopy, as well as with quartz crystal microbalance for in situ and real-time measurements. Large amounts of protein are adsorbed and then nearly completely desorbed on mixed PEO/PAA brushes by a simple pH and I trigger. The mixed brushes thus nicely combine the properties of pure PAA and pure PEO brushes. These adsorption/desorption cycles are shown to be repeated with high efficiency. The high-performance smart substrates created here could find applications in domains as diverse as biosensors, drug delivery and nanotransport. [ABSTRACT FROM AUTHOR]