Liquid Absorption Research Articles

Ultra‐thin benzalkonium chloride‐doped poly(lactic acid) electrospun mat

AbstractIn this study, poly(lactic acid), poly(ethylene glycol), and benzalkonium chloride with different concentrations (3, 5, 7, and 9%wt.) (PLA/PEG/BCL) composite electrospun mats were produced. PLA is a non‐toxic polymer with high biocompatibility and biodegradability. However, it may be fragile due to its structure. Therefore, in this study, PEG was used as a plasticizer to improve the structural properties of PLA and it was aimed at providing antibacterial properties by adding BCL salt. Its use as an antibacterial composite nanomaterial effective against Gram‐positive Staphylococcus aureus (S. aureus) and Gram‐negative Escherichia coli (E. coli) bacterial cultures and as a dermal wound dressing material has been examined in two different areas. The addition of BCL salt reduced the bead formation in PLA/PEG nanofibers and increased the homogeneity of fiber dispersion. 9% BCL‐doped composite nanofiber was obtained as the smoothest and most homogeneous surface. This mat was reported to have the highest ductility. The low Tm of pure BCL salt enabled the Tg temperature of PLA/PEG/BCL composite nanofibers to be observed. It was observed that as the BCL salt ratio increased, the T5 and T10 temperatures of the nanofibers decreased and then increased. BCL‐doped mats exhibited liquid absorption behavior in the range of 497%–708%. PLA/PEG/BCL composite nanofibers showed high toxicity to the L929 fibroblast cell line. So, it has been reported that it cannot be used as a dermal wound dressing. PLA/PEG/BCL composite nanomaterials were reported to have 99.99% antibacterial activity against E. coli and S. aureus. It was suggested that it could be used in antibacterial coating applications by taking into account modern nanocoating technology.Highlights Poly(lactic acid), poly(ethylene glycol), and benzalkonium chloride (PLA/PEG/BCL) composite electrospun mats were produced. The addition of BCL salt reduced the bead formation in PLA/PEG nanofibers and increased the homogeneity of fiber dispersion. 9% BCL‐doped composite nanofiber was obtained as the smoothest and most homogeneous surface. PLA/PEG/BCL composite nanofibers showed high toxicity to the L929 fibroblast cell line. PLA/PEG/BCL composite nanomaterials were reported to have 99.99% antibacterial activity against E. coli and S. aureus.

A study on degradation and CO2 capture performance of aqueous amino acid salts for direct air capture applications

AbstractWe have previously proposed amino acid salts solutions as potential absorption liquids for direct air capture (DAC) of CO2 from the atmosphere. However, little is known about their relevant CO2 solubilities, CO2 mass transfer rates, and susceptibility to oxidative and thermal degradation under conditions relevant to DAC. We report here on the overall solubility of CO2 and CO2 mass transfer rates into a series of amino acid salts solutions. Additionally, the robustness of various amino acid salt solutions to thermal and oxidative degradation has been assessed.CO2 absorption rates into the amino acid salts solutions were observed to be in the same order of magnitude as aqueous monoethanolamine (MEA), with sarcosinate and lysinate solutions providing the fastest and slowest CO2 mass transfer rates at 25°C, respectively. Degradation data revealed that all amino acid salt solutions investigated in this study displayed elevated rates of thermal degradation at both 120 and 150°C relative to MEA. The opposite trend was observed with respect to oxidative degradation where all amino acid salt solutions showed a greater resistance to oxidative degradation than that observed for MEA under the conditions investigated here. Considering the degradation, CO2 absorption capacity, and CO2 mass transfer rate data, we propose the potassium salts of proline and sarcosine as the most promising amino acid salts (of those considered here) for further evaluation in DAC processes. Overall, this study provides valuable insight into the suitability of various amino acid salt solutions as absorption liquid for DAC. © 2024 The Author(s). Greenhouse Gases: Science and Technology published by Society of Chemical Industry and John Wiley & Sons Ltd.

Self-assembled composite fabrics of lotus stem fiber with ultra-high liquid absorption properties

Self-assembled composite fabrics of lotus stem fiber with ultra-high liquid absorption properties

Absorptive Capacity of Gingival Retraction Cords in Hemostatic Solutions: An In Vitro Study.

Background and Objectives: Gingival retraction is a critical pre-impression procedure in fixed prosthodontics, crucial for exposing tooth margins and ensuring accurate impressions for restorations like crowns and bridges. This study aimed to evaluate the absorptive capacity of different gingival retraction cords. Materials and Methods: Ninety samples each of Ultrapak (Ultradent, South Jordan, UT, USA) #00, braided cord, coreless thread, and monofilament thread (totaling 270 samples) were immersed in 0.9% NaCl, 10% aluminum chloride, and 12.7% ferrous sulfate solutions for 120, 300, and 1200 s. The liquid absorption capacity was measured using a gravimetric method, and the data were analyzed using an F-test, setting the significance threshold at p < 0.05. Results: The results revealed statistically significant differences in absorption, particularly for aluminum chloride and ferric sulfate (p < 0.001). Ultrapak demonstrated the highest absorption, followed by the coreless cotton thread, while the monofilament thread absorbed the least, especially at 1200 s. Conclusions: These findings indicate that Ultrapak's superior absorption could enhance moisture control during procedures, highlighting the importance of selecting an appropriate retraction cord for optimal clinical outcomes. Further research is needed to confirm these findings in a clinical setting.

Assessment of the Potential of Electrochemical Steps in Direct Air Capture through Techno-Economic Analysis.

Direct air capture (DAC) technologies are proposed to reduce the atmospheric CO2 concentration to mitigate climate change and simultaneously provide carbon as a feedstock independent of fossil resources. The currently high energy demand and cost of DAC technologies are challenging and could limit the significance of DAC processes. The present work estimates the potential energy demand and the levelized cost of capture (LCOC) of liquid solvent absorption and solid adsorption DAC processes in the long term. A consistent framework is applied to compare nonelectrochemical to electrochemical DAC processes and estimate the LCOC depending on the electricity price. We determine the equivalent cell voltage needed for the electrochemical steps to achieve comparable or lower energy demand than nonelectrochemical processes. The capital expenses (CapEx) of the electrochemical steps are estimated using analogies to processes that are similar in function. The results are calculated for a range of initial data of CapEx and energy demand to include uncertainties in the data.

Graph transformer based transfer learning for aqueous pKa prediction of organic small molecules

The acid-base dissociation constant (pKa) is an essential physicochemical parameter that indicates the extent of proton dissociation. However, accurately predicting pKa values is still challenging due to limited data availability for organic small molecules in aqueous solutions. In this work, we propose an open-source pKa prediction tool based on Graph Transformer, which combines the graph neural network and transformer to take both local and global information into account. To address the limitation of data scarcity, the experimental dataset is expanded, while transfer learning is employed by pre-training on the ChEMBL (computational) dataset and fine-tuning on the experimental dataset. The performance and generalization of the obtained models are comprehensively evaluated on both internal and external test sets. Additionally, two exemplary applications, namely the screening of tertiary amines for CO2 absorption and acidic ionic liquids for reactive extraction, are investigated to validate the reliability of our tool. The results show that our model can effectively guide the identification of promising candidates for the target applications by achieving accurate pKa predictions.

The influence of nano-silica composite superabsorbent polymer on the autogenous shrinkage of mortar

To address the diminished shrinkage reduction capacity due to high ion sensitivity of superabsorbent polymers (SAP) within cement-based materials, this study employs solution polymerization where acrylic acid and acrylamide are copolymerized with nano-silica at varying concentrations to synthesize innovative SAPs. The investigation encompasses the structural groups, microscopic morphology, liquid absorption characteristics of these SAPs, and their effect on mortar's autogenous shrinkage. The results indicate that nano-silica can be encapsulated within polyacrylate-acrylamide network via physical adsorption and chemical grafting. The incorporation of nano-silica enhances the water absorption and retention capacities of SAPs in alkaline environments. Nano-silica composite SAPs absorb sufficient internal curing water and prolong the subsequent moisture gradient-driven water release process, continuously releasing water within matrix to maintain internal humidity, thereby further enhancing the shrinkage reduction effect on mortar. Based on Scanning Electron Microscopy (SEM) observations of SAPs morphologies within mortar and X-ray Computed Tomography (X-CT) monitoring of internal curing water distribution, it is revealed that nano-silica undergoes pozzolanic reactions, forming a tightly connected domain with matrix. This facilitates continuous water release to the surrounding through capillary action, thus maintaining capillary pore liquid levels. Consequently, it effectively mitigating shrinkage stress and deformation, leading to an enhancement in shrinkage reduction effects.

Electrospun high hydrophilicity antimicrobial poly (lactic acid)/silk fibroin nanofiber membrane for wound dressings

Antimicrobial wound dressings can aid wound healing by preventing bacterial infection. This is particularly true of electrospun ones, which have a porous structure and can be easily loaded with antimicrobial drugs. Here, Poly lactic acid (PLA), Silk Fibroin (SF) and antimicrobial agents of Silver nanoparticles (Ag NPs) and Silver oxide (Ag2O) to prepare the PLA/SF composites antimicrobial nanofiber membrane by electrospinning. The PLA with 30 % SF nanofiber membrane show the water vapor permeability (WVP) and the liquid absorption of 36 g·mm/(m2·d·kPa) and 1721 %. With the increasing of SF contents, the degradation rate and surface hydrophilicity of the nanofiber membrane increase significantly. The nanofiber membrane exhibited excellent antimicrobial activity against Pseudomonas aeruginosa (P. aeruginosa) with the inhibition circle reach at 18.2 mm. The resultant nanofiber membrane showed high cytosolic activity, good cytocompatibility and strong antimicrobial ability, which laid a theoretical foundation for the construction of a new PLA/SF composites antimicrobial fiber membrane.

Bio-artificial dura mater in head trauma patients based on a kombucha-chitosan-collagen combination

Introduction: Kombucha scoby shows potential as a biomaterial applicable to patients with head trauma that results in tearing of the dura mater layer. This research aims to characterize kombucha scoby with chitosan and collagen as in vitro modification materials. The artificial dura mater is derived from kombucha scoby synthesized in green tea media and added with glycerol as a plasticizer. Objective: This study used four composition variations: Scoby-Kombucha (Control), Kombucha-Glycerol, Kombucha-Chitosan-Glycerol, and Kombucha-Chitosan-Collagen-Glycerol. Characterization was performed based on functional group analysis through Fourier Transform Infrared (FTIR) testing, tensile strength, swelling, degradation, Scanning Electron Microscope (SEM), and (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) (MTT Assay). The characterization of functional groups confirmed the presence of functional groups from kombucha Scoby, chitosan, collagen, and glycerol. The data were analyzed using descriptive analysis. Results: The results of tensile strength characterization showed that the three sample composition variations have UTS values (4-20 MPa) and Elongation (7-20%) in accordance with artificial dura mater standards. The swelling characterization of the four samples showed a liquid absorption value that does not exceed the swelling ratio limit (&lt;70%). The highest degradation was obtained in the Kombucha-Chitosan-Collagen-Glycerol sample composition with a degradation rate of 20%. The SEM test found a pore diameter that meets the standards for artificial dura mater in the sample compositions of Kombucha-Chitosan-Glycerol and Kombucha-Chitosan-Collagen-Glycerol. Cytotoxicity characterization through the MTT Assay showed that the material does not contain substances toxic to the body. Conclusion: The Kombucha-Chitosan-Collagen-Glycerol membrane was an optimal composition as a candidate for artificial dura mater.

3D‐Printed Hydrogel Filter for Biocatalytic CO2 Capture

AbstractInnovative scalable CO2 capture technologies are urgently needed to combat the climate crisis. Reactive absorption in alkaline liquids, an essential process for capturing CO2 at atmospheric pressure, requires high gas–liquid contact and fast reaction kinetics. To meet these needs, self‐supporting hydrogel CO2 gas–liquid contactors (or simply “CO2 filters”) containing the CO2 selective catalyst carbonic anhydrase (CA) are developed using the direct ink writing additive manufacturing approach. The multifunctional filters are composed of semi‐interpenetrating polymer network hydrogels (IPNHs) of poly (ethylene glycol) diacrylate/poly (ethylene oxide) (PEG‐DA/PEO) upon photocuring during 3D printing. Formulations with PEG‐DA levels of 30–60 wt% are sufficiently homogeneous and reactive to produce coherent grids. Based on operational parameters, a 56 wt% PEG‐DA formulation is selected to continuously print self‐supporting 3D stacked cylindrical grids, with or without enzymes in ink. The resulting enzyme‐laden IPHN filters deliver ≈3 times higher CO2 capture efficiency than the no‐enzyme control filters in a laboratory‐scale absorption column test. However, the enhancement effect decreases significantly within 2 d of operation, likely due to burst release of enzymes caused by the flowing solution. Covalent crosslinking of CA near the surface, which can improve durability and CO2 capture performance, will be evaluated in future studies.

Dynamic and interfacial properties for dichloromethane absorption in ionic liquids: Experimental and molecular dynamic insights

In this study, a strategy for dichloromethane (DCM) capture using ionic liquids (ILs) was systematically investigated from the perspective of dynamic analysis. The diffusion coefficient, Henry’s law constant (H), saturated absorption capacity, and overall volumetric liquid-side mass-transfer coefficient (KLao) of four types of ILs were obtained. Among all the ILs studied, tetrabutylphosphonium caproate ([P4444][C5COO]) demonstrated superior DCM absorption capabilities, and its corresponding H value (3.13 Pa m3/mol at 25 °C) was markedly lower than those of solvents documented in the literature. Furthermore, its KLao value was determined to be 2.77 × 10−3/s at 25 °C, which was measured in a customized cylindrical absorption bottle with a height of 150 mm and an inner diameter of 16 mm. The absorption bottle, fitted with a gas inlet tube having an inner diameter of 5 mm and positioned 5 mm above its base, utilized a simple bubbling technique to introduce gas into the liquid phase, eliminating the need for gas-dispersion equipment. Nevertheless, ILs with high affinities showed relatively high initial mass-transfer rates for DCM. Based on molecular dynamics (MD) simulations, the vapor–liquid interface properties, including mass and number density profiles, molecular orientation, and surface tension, were investigated. This revealed that in the pure [P4444][C5COO] system, the alkyl chain of the anion was oriented toward the gas phase, while the carboxyl group was oriented toward the bulk. The tilt angle of [C5COO]− with respect to the interface was within the range of 37° < θ′ < 70°. For the [P4444][C5COO]/DCM mixture, at the interface, the anion exhibits an enhanced ordered orientation, while the cation shows a more disordered orientation.

Effects and Modification Mechanisms of Different Plasma Treatments on the Surface Wettability of Different Woods

Plasma treatment of wood surfaces has shown significant effects, but different excitation methods used for different species of wood generally result in varied characteristics of wood surfaces. Secondly, plasma modification greatly enhances the absorption of liquids by wood, but the relationship between liquid absorption and surface wettability is rarely studied. Limited detailed investigation of the modification effects and mechanisms has hindered the large-scale applications of plasma treatment in the wood industry. In this study, two typical plasmas, radio frequency (RF) plasma and gliding arc discharge (GAD) plasma, were employed to treat three species of wood: poplar, black walnut, and sapele. By focusing on changes in the contact angle of the wood surface, an exponential equation fitting method is used to determine the measurement time for contact angles. The research identified that factors contributing to the decrease in contact angle after plasma modification include not only the increase in surface energy but also liquid absorption. SEM and XPS analyses demonstrate that plasma etching accelerated liquid absorption by modifying the surface topography, while the increase in surface energy was due to the addition of oxygen-containing groups. High-valence C=O and O-C=O groups serve as indicators of plasma-induced surface chemical reactions. RF modification primarily features surface etching, whereas GAD significantly increases the active surface groups. Thus, different plasmas, due to their distinct excitation modes, produce diverse modification effects on wood. Considering the various physical and chemical properties of plasma-modified wood surfaces, recommendations for adhesive use on plasma-modified wood are provided.

Characterization of wood fiber insulation for the development of wood fiber-insulated panels (WIPs) for use in building envelope

Wood fiber insulation (WFI) was studied as an eco-friendly alternative for fossil-based building insulation, focusing on its use in new wood fiber-insulated panels (WIPs). Rigid WFI boards with densities of 110, 140, and 180 kg/m³, including a 140 kg/m³ variant without paraffin wax, were evaluated. Key properties investigated included porosity, water vapor transmission, liquid water adsorption, and thermal conductivity. The porosity ranged between 85 and 92%, primarily influenced by density. Water vapor permeability ranged from 65 to 90 ng·s-1m-1Pa-1, while liquid water absorption was between 2.5 and 20% by volume, influenced by both wax and density. The thermal conductivity coefficient ranged from 0.038 to 0.055 W/(m·K). Bond strength tests with WFI (140 kg/m³ with wax) laminated to various materials using structural adhesives showed tensile perpendicular-to-grain strengths of 10 to 16 kPa and shear strengths of 60 to 90 kPa, with failure only occurring within the WFI. It was concluded that WFI is a promising material for novel WIPs, offering competitive hygrothermal properties and compatibility with structural adhesives. However, its bio-based nature suggests variability and complexity, necessitating further rigorous testing in various climates and in more complex assemblies.

Transverse emittance reduction in muon beams by ionization cooling

AbstractAccelerated muon beams have been considered for the next-generation studies of high-energy lepton–antilepton collisions and neutrino oscillations. However, high-brightness muon beams have not yet been produced. The main challenge for muon acceleration and storage stems from the large phase-space volume occupied by the beam, derived from the production mechanism of muons through the decay of pions. The phase-space volume of the muon beam can be decreased through ionization cooling. Here we show that ionization cooling leads to a reduction in the transverse emittance of muon beams that traverse lithium hydride or liquid hydrogen absorbers in the Muon Ionization Cooling Experiment. Our results represent a substantial advance towards the realization of muon-based facilities that could operate at the energy and intensity frontiers.

Full micro-nanofiber aerogel with three-dimensional fluffy network structure for rapid liquid absorption and uniform liquid retention in diapers

Diapers are essential for infants and patients with urinary incontinence. The super-absorbent polymer (SAP) in the core layer of diapers suffers from slow liquid absorption, fault formation, and reverse osmosis. Therefore, it is desirable to construct a core layer that can integrate rapid liquid absorption, uniform retention, and anti-seepage qualities. In this study, a diaper core layer and a three-dimensional fluffy network structure with a wetting gradient was constructed via one-step solution blow spinning (SBS). By regulating the content of the glutaraldehyde (GA) cross-linking agent, absorbent and insoluble fibers could be obtained. The ratio of super-absorbent fibers (SAF) to PAN-PVP micro-/nano fibers in the three-layer fiber structure and the gram weight of the core layer were adjusted. A wetting gradient was established when the weight of the adjusted gradient core layer was 2/3 that of the commercial core layer. The amount of reverse osmosis was reduced by 0.25 g, and the liquid absorption and retention were 30 times and 28.5 times, respectively, two and 3.5 times higher than those of commercial diapers. The SAF prepared by SBS could improve the core layer's liquid absorption rate, retention ratio, and comfort. The fibers are applicable in diapers, sanitary napkins, and other disposable products.

Highly Compressible, Superabsorbent, and Biocompatible Hybrid Cryogel Constructs Comprising Functionalized Chitosan and St. John's Wort Extract.

Biobased porous hydrogels enriched with phytocompounds-rich herbal extracts have aroused great interest in recent years, especially in healthcare. In this study, new macroporous hybrid cryogel constructs comprising thiourea-containing chitosan (CSTU) derivative and a Hypericum perforatum L. extract (HYPE), commonly known as St John's wort, were prepared by a facile one-pot ice-templating strategy. Benefiting from the strong interactions between the functional groups of the CSTU matrix and those of polyphenols in HYPE, the hybrid cryogels possess excellent liquid absorption capacity, mechanical resilience, antioxidant performance, and a broad spectrum of antibacterial activity simultaneously. Thus, owing to their design, the hybrid constructs exhibit an interconnected porous architecture with the ability to absorb over 33 and 136 times their dry weight, respectively, when contacted with a phosphate buffer solution (pH 7.4) and an acidic aqueous solution (pH 2). These cryogel constructs have extremely high compressive strengths ranging from 839 to 1045 kPa and withstand elevated strains of over 70% without developing fractures. Moreover, the water-swollen hybrid cryogels with the highest HYPE content revealed a complete and instant shape recovery after uniaxial compression. The incorporation of HYPE into CSTU cryogels enabled substantial improvement in scavenging reactive oxygen species and an expanded antibacterial spectrum toward multiple pathogens, including Gram-positive bacteria (Staphylococcus aureus and Staphylococcus epidermidis), Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa), and fungi (Candida albicans). Cell viability experiments demonstrated the cytocompatibility of the 3D cryogel constructs, which did not induce changes in the fibroblast morphology. This work showcases a simple and effective strategy to immobilize HYPE extracts on CSTU 3D networks, allowing the development of novel multifunctional platforms with promising potential in hemostasis, wound dressing, and dermal regeneration scaffolds.

Mass transfer of gas–liquid two‐phase flow in asymmetric parallel microchannels with liquid feed splitting

AbstractDue to size limitations, the gas–liquid absorption capacity of a single microchannel is limited, making it difficult to achieve large‐scale CO2 capture. Therefore, the parallel microchannels combining the advantages of high efficiency and large throughput stand out. However, when the operating condition is high gas–liquid flow rate ratio, the liquid phase between bubbles almost disappears after multiple distributions, which affects the amount of gas–liquid absorption. In this study, the numbering‐up of the asymmetric parallel microchannels in the gas–liquid absorption process was investigated by splitting the liquid feed stream in two. The flow patterns under different operating conditions were obtained. The flow and distribution of gas–liquid two‐phase flow were investigated, and the reason of the distribution deterioration caused by appearance of long slug bubbles was explained by the pressure drop distribution. The total liquid mass transfer coefficient and bubble residence time were derived and obtained, and the mass transfer was further discussed.

Deep Low-Carbon Economic Optimization Using CCUS and Two-Stage P2G with Multiple Hydrogen Utilizations for an Integrated Energy System with a High Penetration Level of Renewables

Integrating carbon capture and storage (CCS) technology into an integrated energy system (IES) can reduce its carbon emissions and enhance its low-carbon performance. However, the full CCS of flue gas displays a strong coupling between lean and rich liquor as carbon dioxide liquid absorbents. Its integration into IESs with a high penetration level of renewables results in insufficient flexibility and renewable curtailment. In addition, integrating split-flow CCS of flue gas facilitates a short capture time, giving priority to renewable energy. To address these limitations, this paper develops a carbon capture, utilization, and storage (CCUS) method, into which storage tanks for lean and rich liquor and a two-stage power-to-gas (P2G) system with multiple utilizations of hydrogen including a fuel cell and a hydrogen-blended CHP unit are introduced. The CCUS is integrated into an IES to build an electricity–heat–hydrogen–gas IES. Accordingly, a deep low-carbon economic optimization strategy for this IES, which considers stepwise carbon trading, coal consumption, renewable curtailment penalties, and gas purchasing costs, is proposed. The effects of CCUS, the two-stage P2G system, and stepwise carbon trading on the performance of this IES are analyzed through a case-comparative analysis. The results show that the proposed method allows for a significant reduction in both carbon emissions and total operational costs. It outperforms the IES without CCUS with an 8.8% cost reduction and a 70.11% reduction in carbon emissions. Compared to the IES integrating full CCS, the proposed method yields reductions of 6.5% in costs and 24.7% in emissions. Furthermore, the addition of a two-stage P2G system with multiple utilizations of hydrogen further amplifies these benefits, cutting costs by 13.97% and emissions by 12.32%. In addition, integrating CCUS into IESs enables the full consumption of renewables and expands hydrogen utilization, and the renewable consumption proportion in IESs can reach 69.23%.

Films based on TEMPO-oxidized chitosan nanoparticles: Obtaining and potential application as wound dressings

A series of novel films based on TEMPO-oxidized chitosan nanoparticles were prepared by casting method. Fourier transform infrared spectroscopy (FTIR) was employed to ascertain the chemical structure of TEMPO-oxidized chitosan. The surface morphology of the TEMPO-oxidized chitosan nanoparticles was analyzed by atomic force microscopy (AFM). The physicochemical (area density, thickness, iodine sorption, roughness), functional (moisture sorption, liquid absorption capacity, weight loss upon contact with the liquid, and water vapor transmission rate), antibacterial, and antioxidant properties of films based on TEMPO-oxidized chitosan nanoparticles were also investigated. The physicochemical properties of the films varied widely: area density ranged from 77.83 ± 0.06 to184.46 ± 0.05 mg/cm2, thickness varied between 80.5 ± 1.6 and 200.5 ± 1.6 μm, iodine sorption spanned from 333.7 ± 2.1 to166.4 ± 2.2 mg I2/g, and roughness ranged from 4.1 ± 0.2 to 5.6 ± 0.3 nm. Similarly, the functional properties also varied significantly: moisture sorption ranged from 4.76 ± 0.03 to 9.62 ± 0.11 %, liquid absorption capacity was between 129.04 ± 0.24 and 159.33 ± 0.73 % after 24 h, weight loss upon contact with the liquid varied between 31.06 ± 0.35 and 45.88 ± 0.58 % after 24 h and water vapor transmission rate ranged from 1220.10 ± 2.91to1407.77 ± 5.22 g/m2 day. Despite the wide variations in physicochemical and functional properties, all films showed maximum bacterial reduction of Staphylococcus aureus and Escherichia coli, although they exhibited low antioxidant activity. The results suggest that the films could be effectively utilized as antibacterial wound dressings.

Permeability and barrier layer properties of a woven carbon fibre polymer composite as battery packaging

Carbon fibre reinforced polymer (CFRP) laminates are used in various studies as Li-ion polymer (LiPo) battery packaging. However, their suitability as a packaging material is not well understood. The present study investigates the liquid absorption (water and lithium bis(trifluoromethanesulfonic)imide (LiTFSI) electrolyte immersion tests) and barrier layer properties (water vapour transmission rate (WVTR) and oxygen transmission rate (OTR) tests) of a 200 gsm woven CFRP laminate to assess its suitability as a battery packaging material. This is the first study to show that prolonged immersion in battery electrolyte does not change the mechanical properties of a woven CFRP laminate. Hence, the CFRP laminate may be suitable for structural battery components, such as current collectors and electrodes. However, CFRP should not be used as battery packaging, as OTR and WVTR values of the CFRP laminate were found to be five and one order of magnitudes higher than typical battery pouch materials (i.e. aluminium foil), respectively.