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Highlighted with bio‐degradability, paper‐based flexible pressure sensors receive significant attention in the field of wearable devices for a sustainable future. However, it remains a challenge to possess considerable sensing performance in high humidity and underwater environments, because its structure rapidly breaks down after the hydrophilic cellulose absorbs water. In this study, a facile chemical vapor deposition method is employed to conformally coat a thin hydrophobic layer onto the cellulose fibers, resulting in an encapsulating paper with high moisture tolerance. The well‐maintained porous structure reserves the superior breathability of the paper. A micro‐convex‐structured sensor layer impregnated with MXene serves as the sensing layer. As a result, an all‐paper‐based pressure sensor with high moisture tolerance and breathability is fabricated. This sensor features a broad sensing range (0–60 kPa), acceptable sensitivities (39.58 kPa−1 (0–1.01 kPa), 11.95 kPa−1 (1.01–60 kPa)), a low detection limit of ≈2.8 Pa, response and recovery time (93 and 69 ms), reliable hydrophobic breathability, and excellent repeatability (10 000 cycles). Moreover, this sensor can be safely worn on human skin and can monitor physiological signals in real‐time in different environments (including air, humid environments, and even underwater), providing a reliable, economical, and environmentally friendly solution for wearable technology. [ABSTRACT FROM AUTHOR]

[Display omitted] Moist-electric generators (MEGs), which are capable of spontaneously generating energy from ubiquitous moisture, are considered as a potential power supply candidate for wearable electronics. However, the application of the MEGs in the wearable field is still challenging due to the low electric output and the lack of wearable attributes such as breathability and flame retardancy. Herein, we demonstrated a wearable MEG with high power-output, breathability and flame retardancy, which was fabricated by designing an asymmetrical nanofiber assembly using hydrophilic polyvinyl alcohol/phytic acid (PVA/PA) and hydrophobic polyvinylidene difluoride (PVDF) nanofiber membranes. Owing to the synergistic effects of strong water absorption, enhanced ion release and numerous micro-nano transport channels, a single MEG of 1 cm2 could constantly generate high direct-current (DC) power, i.e., a voltage of 1.0 V, a current of 15.5 μA, and a power density of 3.0 μW cm−2, outperforming other reported nanofiber-based MEGs. More importantly, the asymmetric nanofiber structure ensured the moisture circulation inside MEG and thus produced a sustained voltage output for 7 days without any deterioration. The MEG also showed good flexibility, air/moisture permeability and flame retardancy, which give it necessary wearable attributes. Furthermore, large-scale integration of MEG units could be readily realized to fabricate a power source device for driving different portable electronics, while the moisture sensitivity made the MEG well used for sensing applications (e.g., respiration monitoring, fire warning). [ABSTRACT FROM AUTHOR]

For the need of direct contact with the skin, electronic skins (E‐skins) should not only fulfill electric functions, but also ensure comfort during wearing, including permeability, waterproofness, and easy removal. Herein, the study has developed a self‐adhesive, detach‐on‐demand, breathable, and waterproof E‐skin (PDSC) for motion sensing and wearable comfort by electrospinning styrene‐isoprene block copolymer rubber with carbon black nanosheets as the sensing layer and liner copolymers of N, N‐dimethylacrylamide, n‐octadecyl acrylate and lauryl methacrylate as the adhesive layer. The high elasticity and microfiber network structure endow the PDSC with good sensitivity and high linearity for strain sensing. The hydrophobic and crystallizable adhesive layer ensures robust, waterproof, and detaching‐on‐demand skin adhesion. Meanwhile, the fiber structure enables the PDSC good air and water permeability. The integration of electric and wearable functions endows the PDSC with great potential for motion sensing during human activities as both the sensing and wearable performances. [ABSTRACT FROM AUTHOR]

AbstractNon-medical masks such as disposable non-medical, commercially produced cloth, and homemade masks are not regulated like surgical masks. Their performance, in terms of filtration efficiency and breathability, is variable and unreliable. This research provides a quantitative evaluation of various non-medical masks, assesses their fabrics’ potential for the reduction of transmission of bioaerosols such as the SARS-CoV-2 virus, and compares them to surgical masks and N95 filtering facepiece respirators. Using a testing line with a NaCl challenge aerosol, four types of commercial reusable cloth masks, two types of disposable non-medical masks, three types of surgical or N95 masks, and seven types of commonly available materials were tested individually and in combinations. The testing line and procedure were adapted from the ASTM F2299-03: Standard Test Method for Determining the Initial Efficiency of Materials Used in Medical Face Masks to Penetration by Particulates Using Latex Spheres testing method used for testing surgical masks. Filtration efficiencies at 0.15 µm particle diameter at a face velocity of 25 cm/sec for commercial cloth masks, disposable non-medical masks, surgical masks, commercial mask combinations, and homemade combinations ranged from 16–29%, 39–76%, 91–97%, 51–95%, and 45–94%, respectively. The pressure drop results for the different masks and material combinations were all under 3 mm H2O/cm2 except for one material configuration. This study builds on other research that looks at individual materials and masks by testing combinations alongside the individual masks and materials. With proper layering, household materials can achieve the filtration efficiency and low pressure drop requirements of surgical masks. The filtration capabilities of disposable and cloth mask fabrics vary considerably meaning that they are not a reliable or consistent facemask option, regardless of fit. [ABSTRACT FROM AUTHOR]

This study presents the development of multifunctional protective clothing for disabled individuals using PBAT/PLA biopolymeric-based electrospun nanofibrous membranes. The fabric consists of a superhydrophobic electrospun nanofibrous cloth reinforced with silica nanoparticles. The resulting nanofiber membranes were characterized using FE-SEM, a CA goniometer, breathability and hydrostatic pressure resistance tests, UV–vis spectroscopy, thermal infrared photography, tensile tests, and nanoindentation. The results demonstrated the integration of superhydrophobicity, breathability, and mechanical improvements in the protective clothing. The nanofibrous porous structure of the fabric allowed breathability, while the silica nanoparticles acted as an effective infrared reflector to keep the wearer cool on hot days. The fabric's multifunctional properties make it suitable for various products, such as outdoor clothing and accessories for individuals with disabilities. This study highlights the importance of selecting appropriate textiles for protective clothing and the challenges faced by disabled individuals in terms of mobility, eating, and dressing. The innovative and purposeful design of this multifunctional protective clothing aimed to enrich the lives of individuals with disabilities. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate and design masks against viruses, especially SARS-CoV-2 associated with COVID-19. A continuum filtration model was developed where the rate of particle deposition and "sticking" on the filter fibers is a critical term in the mass transfer, together with permeation velocity, filter porosity, tortuosity, and Brownian diffusion. CFD simulations of the airflow during respiration lead to the recommendation that the filter permeability should be above 4 × 10−11 m2 to direct the airflow for effectiveness against virus particles; otherwise, low filter permeabilities cause the unfiltered air to flow preferentially through the leak gaps between the mask and the headform. Different mask filters with microstructural and geometry data from the literature are assessed via filtration simulations for breathability and filtration efficiency. The results demonstrate that a surgical mask of 25% porosity, pore size of 150 µm and permeability of 4.4 × 10−11 m2 can achieve 100% minimum efficiency while demonstrating high breathability, complying with the criteria of FFP3, N95, and surgical Class II and IIR masks. Selected cotton and synthetic cloths as well as electrospun fiber layers are predicted to comply with FFP2, N95, and surgical mask Class II and IIR standards. [ABSTRACT FROM AUTHOR]

Textiles incorporating phase change material have attracted increasing attention due to their temperature regulating function. Although a great progress has been made in the development of phase change material textiles, it has been found that the loading amount of phase change materials is limited by other final properties. Recently, we have proposed a sandwich fibrous phase change material encapsulation with a relatively high phase change material loading amount, which is a multi-layer fabric structure containing phase change material. However, the breathability of sandwich fibrous phase change material encapsulation should be improved because there is no path for air to penetrate through. In this work, the sandwich fibrous phase change material encapsulation structure with polyethylene glycol as phase change material is modified by introducing different air pockets in the thermal function layer ranging from 19% to 64%. The leakage phenomenon, phase transition behavior, thermal energy storage, breathability, T-history and practicality of the breathable sandwich fibrous phase change material encapsulations are investigated. As a result, the maximum polyethylene glycol loading amount of the phase change materials pocket is 83 wt%, and there is no leakage of polyethylene glycol during working time. The overall enthalpy value of the breathable sandwich fibrous phase change material encapsulation ranges from 27 J/g to 48 J/g. The optimal air permeability and water vapor resistance of the breathable sandwich fibrous phase change material encapsulation is 9 mm/s under 100 Pa and 34.5 m2 Pa W−1. Furthermore, the heterogeneous heat transfer through the breathable sandwich fibrous phase change material encapsulation is found due to the complicated thermal resistances of the hybrid thermal functional layer. In addition, for breathable sandwich fibrous phase change material encapsulation, the flexibility, hydrophobicity, self-cleaning property, abrasion resistance, and stability after water immersion are found. We believe the research has a great potential in various applications related to phase change material. [ABSTRACT FROM AUTHOR]

The transfer of water vapor through a textile is a crucial factor for ensuring comfort and performance in various applications that involve exposure to moisture or sweating, including military, firefighting, and outdoor sports activities. This work proposes a new experimental setup to measure the water vapor resistance of fabrics under different temperature and humidity conditions, providing more realistic values compared to conventional steady-state methods. Two different fabrics were analyzed. The first one is a common blend of fibers that mainly contains cotton (95 %) and elastane (5 %), and the second one contains modacrylic fibers (MAC Protex® 60 %) in combination with cotton (40 %). The results showed that the predominance of cotton in the composition of the fabric can lead to an increase of up to 13 % in the resistance to vapor transfer, attributed to the swelling effect of the fibers due to the increase in relative humidity. Blending cotton and PROTEX fibers in such fabrics provides improved moisture management properties in the sense of maintaining constant water vapor resistance even as relative humidity increases, contributing to wearer dryness and comfort. [ABSTRACT FROM AUTHOR]

Electronic textiles (E-textiles) have experienced an increase in interest in recent years leading to a variety of new concepts emerging in the field. Despite these technical innovations, there is limited literature relating to the testing of E-textiles for some of the fundamental properties linked to wearer comfort. As such, this research investigates four fundamental properties of E-textiles: air permeability, drape, heat transfer, and moisture transfer. Three different types of E-textiles were explored: an embroidered electrode, a knitted electrode, and a knitted structure with an embedded electronic yarn. All of the E-textiles utilized the same base knitted fabric structure to facilitate a comparative study. The study used established textile testing practices to evaluate the E-textiles to ascertain the suitability of these standards for these materials. The study provides a useful point of reference to those working in the field and highlights some limitations of existing textile testing methodologies when applied to E-textiles. [ABSTRACT FROM AUTHOR]

Antibacterial fiber mats play a crucial role in inhibiting the spread of bacteria and preventing bacterial transmission. While polytetrafluoroethylene (PTFE) exhibits excellent biological inertness, the lack of antibacterial properties in pure PTFE fiber mats has diminished their competitiveness. In this study, we developed an antibacterial fiber mat with high breathability and moisture permeability by introducing silver nanoparticles (Ag NPs) into a PTFE emulsion through electrospinning. In this study, five sets of concentration gradients from 1% to 5% were set up, and the comparison revealed that the best PTFE/Ag NPs composite fiber mat (PA fiber mat) performance was achieved at 3% Ag NPs concentration. Compared to PTFE fiber mats without Ag NPs loading and conventional expanded membranes (ePTFE), it demonstrated antibacterial rates of 97.1% against Escherichia coli (E. coli) and 97.0% against Staphylococcus aureus (S. aureus), a moisture permeability performance of 15,500 ± 304 g(m2·12h)−1, and excellent breathability. The fiber mat exhibited not only outstanding antibacterial capabilities but also a water contact angle of 137.6°, an elongation at break of approximately 260.92%, and a tensile strength of about 1.84 MPa. These properties offer great promise for PA fiber mats in antibacterial fabric applications including medical masks and protective clothing. [ABSTRACT FROM AUTHOR]

Inkjet printing technology has been playing an increasingly important role in manufacturing of electronic devices due to its low cost, high deposition accuracy, and mass manufacturability. Inkjet-printed flexible sensors are increasingly used in the field of flexible/wearable electronics. In this study, a kneadable humidity sensor with high breathability was developed on electrospun thermoplastic polyurethane (TPU) nanofibrous mats using inkjet printing technology. This humidity sensor shows good sensitivity over a wide humidity range, with a resistance change of only 6.13% after 1000 mechanical bends at 75% relative humidity (RH). It also has good reversibility, and the morphology and structure are not damaged upon direct contact with water droplets. In addition, the humidity sensor with good air permeability (28.8 mm s−1) can be used for breath monitoring, particularly for person in sadness, panic, and tensed situations. [ABSTRACT FROM AUTHOR]

Abstract For the need of direct contact with the skin, electronic skins (E‐skins) should not only fulfill electric functions, but also ensure comfort during wearing, including permeability, waterproofness, and easy removal. Herein, the study has developed a self‐adhesive, detach‐on‐demand, breathable, and waterproof E‐skin (PDSC) for motion sensing and wearable comfort by electrospinning styrene‐isoprene block copolymer rubber with carbon black nanosheets as the sensing layer and liner copolymers of N, N‐dimethylacrylamide, n‐octadecyl acrylate and lauryl methacrylate as the adhesive layer. The high elasticity and microfiber network structure endow the PDSC with good sensitivity and high linearity for strain sensing. The hydrophobic and crystallizable adhesive layer ensures robust, waterproof, and detaching‐on‐demand skin adhesion. Meanwhile, the fiber structure enables the PDSC good air and water permeability. The integration of electric and wearable functions endows the PDSC with great potential for motion sensing during human activities as both the sensing and wearable performances.

Global textile production and consumption has increased steadily over the past 15 years, which has caused significant impacts on the climate and the environment. In 2022, the EU launched a strategy for sustainable and circular textiles, stating that extending the life of textile products is the most efficient way to reduce their impact on the climate and the environment. Shell jackets for outdoor use are textile products that are frequently discarded by their first users and re-sold on the second-hand market. This study evaluates the performance of 16 second-hand shell jackets from three second-hand stores in Sweden via material testing of four key functional aspects. Comparing the results with the jackets' original performance, this study describes the change in functionality over time. The results indicate that air permeability does not change significantly, whereas water repellency, water penetration resistance, and breathability decrease over time, although they do so at different rates. With the aim of promoting circularity and encouraging longer product use, this study also compares the price evolution of jackets with their functionality over time. The results reveal that the resale price of the jackets is lower than could be expected based on the level of remaining functionality in the jackets. [ABSTRACT FROM AUTHOR]

Self‐cleaning and anti‐biofouling are both advantages for lotus‐leaf‐like superhydrophobic surfaces. Methods for creating superhydrophobicity, including chemical bonding low surface energy molecular fragments and constructing surface morphology with protrusions, micropores, and trapped micro airbags by traditional physical strategies, unfortunately, have encountered challenges. They often involve complex synthesis processes, stubborn chemical accumulation, brutal degradation, or infeasible calculation and imprecise modulation in fabricating hierarchical surface roughness. Here, a scalable method to prepare high‐quality, breathable superhydrophobic membranes is proposed by developing a successive roll‐to‐roll laser manufacturing technique, which offers advantages over conventional fabrication approaches in enabling automatically large‐scale production and ensuring cost‐effectiveness. Nanosecond laser writing and femtosecond laser drilling produce surface microstructures and micropore arrays, respectively, endowing the membrane with superior antiwater capability with hierarchical microstructures forming a barrier and blocking water infiltration. The membrane's breathability is carefully optimized by tailoring micropore arrays to allow for the adequate passage of water vapor while maintaining superhydrophobicity. These membranes combine the benefits of anti‐aqueous corrosive liquid behaviors, photothermal effects, thermoplastic properties, and stretchable performances as promising comprehensive materials in diverse scenes. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Almaty Technological University is the property of Almaty Technological University 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.)

Textile production is a major component of the global industry, with sales of over USD 450 billion and estimations of an 84% increase in their demand in the next 20 years. In recent decades, protective and smart textiles have played important roles in the social economy and attracted widespread popularity thanks to their wide spectrum of applications with properties, such as antimicrobial, water-repellent, UV, chemical, and thermal protection. Towards the sustainable manufacturing of smart textiles, biodegradable, recycled, and bio-based plastics are used as alternative raw materials for fabric and yarn production using a wide variety of techniques. While conventional techniques present several drawbacks, nanofibers produced through electrospinning have superior structural properties. Electrospinning is an innovative method for fiber production based on the use of electrostatic force to create charged threads of polymer solutions. Electrospinning shows great potential since it provides control of the size, porosity, and mechanical resistance of the fibers. This review summarizes the advances in the rapidly evolving field of the production of nanofibers for application in smart and protective textiles using electrospinning and environmentally friendly polymers as raw materials, and provides research directions for optimized smart fibers in the future. [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.)

Electrospun fibrous structures can be developed superhydrophobic while remaining breathable. However, current electrospinning‐based methods for developing superhydrophobicity require complex fabrication processes and multiple raw materials, lacking a facile approach to superhydrophobicity using electrospun fibers. Inspired by a cultural relic known as Plain Gauze Gown, a fibrous structure consisting two layers of porous fibers aligned in warp and weft directions by simple electrospinning is developed. Through investigation of wetting behavior, an unique Cassie–Baxter‐"restoring" (CaRe) wetting contributing to a stable Cassie–Baxter state is unveiled in the developed structure. The CaRe wetting ensures that droplet stays on the upper‐layer fibers even at a sparse inter‐fiber distance, enabling strategically reaching superhydrophobicity by lowering structure solidity. Remarkably, the developed structure with water contact angle between 159° and 162° and roll‐off angle from 10° to 3° has a water vapor transmission rate of 20.8 kg m−2 d−1, which is the highest value among all superhydrophobic electrospun structures reported, and it is also waterproof and semi‐transparent. These features make the structure suitable for a wide range of applications, including developing waterproof, breathable, and superhydrophobic membrane with simple preparation and low cost, and as a surface layer for wearable electronics that facilitates sweat evaporation and prevents water intrusion. [ABSTRACT FROM AUTHOR]

A notable application of polymeric nanocomposites is the design of water vapor permeable (WVP) membranes. "Breathable" membranes can be created by the incorporation of micro/nanofillers, such as CaCO3, that interrupt the continuity of the polymeric phase and when subjected to additional uniaxial or biaxial stretching this process leads to the formation of micro/nanoporous structures. Among the candidate nanofillers, carbon nanotubes (CNTs) have demonstrated excellent intrinsic WVP properties. In this study, chemically modified MWCNTs with oligo olefin-type groups (MWCNT-g-PP) are incorporated by melt processes into a PP matrix; a β-nucleating agent (β-ΝA) is also added. The crystallization behavior of the nanocomposite films is evaluated by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The WVP performance of the films is assessed via the "wet" cup method. The nanohybrid systems, incorporating both MWCNT-g-PP and β-NA, exhibit enhanced WVP compared to films containing only MWCNT-g-PP or β-NA. This improvement can be attributed to the significant increase in the growth of α-type crystals taking place at the edges of the CNTs. This increased crystal growth exerts a form of stress on the metastable β-phase, thereby expanding the initial microporosity. In parallel, the coexistence of the inherently water vapor-permeable CNTs, further enhances the water vapor permeability reaching a specific water vapor transmission rate (Sp.WVTR) of 5500 μm.g/m2.day in the hybrid composite compared to 1000 μm.g/m2.day in neat PP. Notably, the functionalized MWCNT-g-PP used as nanofiller in the preparation of the "breathable" PP films demonstrated no noteworthy cytotoxicity levels within the low concentration range used, an important factor in terms of sustainability. [ABSTRACT FROM AUTHOR]

In this paper, a new flexible stab-resistant composite material was prepared by growing ZnO nanowires on aramid plain fabric by the hydrothermal method. Through SEM, FTIR, and XRD characterization, it is proved that ZnO nanowires have been grown on aramid fabric and the surfaces of aramid filaments become much rougher. Moreover, the inter-filament friction and breaking strength of aramid fabric with nanowires are increased significantly, especially the inter-filament friction, which has been increased by more than 4 times after ZnO nanowires growth. Stab tests were conducted on the bare aramid fabric sample and aramid fabric sample with ZnO nanowires based on the test standard of GA 68–2019. Both of the two samples are 43 layers and are subject to 5 stabs of D1 knife, 3 stabs of D2 knife and 3 stabs of D3 knife. The stab resistance of aramid fabric grown with nanowires is significantly enhanced, and the average penetration depth under the D1 knife impact is decreased by 49.7%. The reason may be that the inter-filament friction increases dramatically with the nanowires and thus the friction energy consumption increases. The flexibility test results show that the softness characteristics of the single aramid fabric and the 43-layer fabric with the nanowires are still maintained. In addition, although the growth of nanowires will lead to smaller voids and a decrease of air permeability of the fabric, the moisture permeability has been slightly improved because ZnO nanowires have the ability to bind with water.

Abstract Electrospun fibrous structures can be developed superhydrophobic while remaining breathable. However, current electrospinning‐based methods for developing superhydrophobicity require complex fabrication processes and multiple raw materials, lacking a facile approach to superhydrophobicity using electrospun fibers. Inspired by a cultural relic known as Plain Gauze Gown, a fibrous structure consisting two layers of porous fibers aligned in warp and weft directions by simple electrospinning is developed. Through investigation of wetting behavior, an unique Cassie–Baxter‐“restoring” (CaRe) wetting contributing to a stable Cassie–Baxter state is unveiled in the developed structure. The CaRe wetting ensures that droplet stays on the upper‐layer fibers even at a sparse inter‐fiber distance, enabling strategically reaching superhydrophobicity by lowering structure solidity. Remarkably, the developed structure with water contact angle between 159° and 162° and roll‐off angle from 10° to 3° has a water vapor transmission rate of 20.8 kg m−2 d−1, which is the highest value among all superhydrophobic electrospun structures reported, and it is also waterproof and semi‐transparent. These features make the structure suitable for a wide range of applications, including developing waterproof, breathable, and superhydrophobic membrane with simple preparation and low cost, and as a surface layer for wearable electronics that facilitates sweat evaporation and prevents water intrusion.

Electronic skins (E‐skins) capable of biomechanical/bioelectrical signal acquisition are intensively pursued for human‐centered healthcare of daily life. For practical use, it is highly desired, yet challenging, to mass‐produce E‐skins that are soft and breathable for wearing comfort, skin‐adhesive for robust signal acquisition, multi‐signal sensing for enhanced healthcare data. Herein, a scalable fabrication strategy for a bioinspired E‐skin (SPRABE‐skin) with a multi‐layered architecture is reported that integrates skin‐like softness, self‐protection, self‐adhesion, breathability, and bimodal sensing in a single patch. The fibrous thermoplastic polyurethane (TPU) scaffold endows the SPRABE‐skin with tissue‐like softness (Young's modulus of 3.36 MPa) and stretchability, good permeability to water vapor, and self‐protection against adverse loading events. A strain sensing layer composed of MXene‐carbon nanotubes@TPU (MXene‐CNT@TPU) composition exhibits ultra‐high sensitivity in a wide sensing range (gauge factor at strain of 485% reaches 63 494). An electrode layer made of MXene‐waterborne polyurethane (MXene‐WPU) provides a highly adhesive electrode‐skin interface, which enables the acquisition of biopotentials, such as electrocardiograph (ECG), electromyograph (EMG), electroencephalo‐graph (EEG), with improved fidelity even under various dynamic interferences. Finally, a SPRABE‐skin based human‐centered healthcare system is demonstrated that realizes the wireless, long‐duration, and dynamic monitoring of ECG and running activities. [ABSTRACT FROM AUTHOR]

Electrospun nanofibrous membranes have attracted significant interest due to their captivating waterproof and breathable characteristics, stemming from the presence of interconnected and hydrophobic channels within these enhanced textiles. These distinctive traits bestow upon them substantial potential across various domains, encompassing applications in medical dressings, masks, and protective clothing. However, they also give rise to concerns about their durability, compromised waterproofing performance, limited breathability, insufficient mechanical strength, and high production costs. Furthermore, the manufacturing processes of electrospun waterproof and breathable membranes (WBMs) may carry adverse environmental implications, necessitating improvements in sustainability and ecological compatibility. This study begins with a concise overview of the operational principles and criteria for performance evaluation relevant to electrospun WBMs, providing comprehensive guidelines to drive future research. Following this, the authors delve into a thorough exploration of typical fabrication techniques and the prevailing strategies, exemplified by noteworthy ongoing research initiatives. Last, the existing challenges are outlined to foster the development of WBMs. In addition, future research directions and perspectives are presented to expedite the advancement of WBMs and support their commercial implementation. It is anticipated that this comprehensive review will offer pragmatic recommendations for researchers dedicated to the advancement of WBMs. [ABSTRACT FROM AUTHOR]

A perfect protective fabric for handicapped individuals must be lightweight, waterproof, breathable, and able to absorb water. We present a multifunctional protective fabric in which one side is hydrophobic based on the intrinsic hydrophobic biopolymer polylactic acid (PLA) to keep the disabled person from getting wet, while the other side is super-hydrophilic due to embedded silica nanoparticles (NPs) to keep the disabled person safe from a sudden spill of water or other beverage on their skin or clothes. The porosity of the electrospun nanofibrous structure allows the fabric to be breathable, and the silica NPs play an important role as a perfect infrared reflector to keep the person's clothing cool on warm days. Adding white NPs, such as silicon dioxide, onto or into the textile fibers is an effective method for producing thermally insulated materials. Due to their ability to efficiently block UV light, NPs in a network keep the body cool. Such a multifunctional fabric might be ideal for adult bibs and aprons, outdoor clothing, and other amenities for individuals with disabilities. [ABSTRACT FROM AUTHOR]

The elevated use of petroleum-based polymers to manufacture single-use disposable face masks is a serious environmental concern that has detrimental effects on the ecosystem. The research on using biodegradable facemasks is promising to reduce the environmental impacts of the single-use nondegradable facemask. A reusable cloth-based facemask with effective filtration could benefit society. Many studies suggest polyvinyl alcohol (PVA), polybutylene adipate terephthalate (PBAT), and polylactic acid (PLA) as viable biopolymers for facemask filter layer fabrication. In this work, an electrospun filter layer inserts with PVA, PBAT, and PLA polymers were produced by depositing electrospun nanofibers on non-woven cotton layers followed by conventional sealing. The fabricated filter inserts were used in cloth-based facemasks and were tested for filtration efficiencies and breathability. PVA facemask insert showed the best performance with 66.7% filtration efficiency and breathability of 0.66 m bar, whereas the lowest filtration efficiency was found for PBAT electrospun filter medium. The relation between filter membrane morphology and facemask performance indicates that a smaller diameter and uniform morphology results in better filtration and breathability of the facemask filter inserts. [ABSTRACT FROM AUTHOR]

With the growing demand of multifunction membranes with water vapor transmission and breathable performances in many fields, design of multifunction membranes with facile fabrication is crucial and challenging. In this work, a highly breathable bi-layered polyurethanes—polyacrylonitrile/cellulose acetate (PU-PAN/CA) membrane with outstanding water vapor transmission and excellent mechanical property was fabricated by electrospinning. And then, the bi-layered PU-PAN/CA nanofibrous membranes were characterized using SEM, FTIR, tensile stress, water contact angle, air permeability, water vapor permeability and moisture management tester to evaluate the performance. The prepared PU-PAN/CA membrane has a comprehensive performance by adjusting the CA ratio of the PAN/CA layer and electrospinning time of PU layer with breathable of 21.81 mm s−1, water vapor transmission (WVT) rate of 12.18 kg m−2 day−1, and tensile strength of 8.90 MPa, which shows its certain reference significance to the prepared of multifunctional membrane. At the end, the performance of prepared membrane was compared with other membranes. The successful preparation of such interesting bi-layered membranes could provide enlighten for the preparation of other functional fibrous materials, especially in oil/water, directional water transport and moisture-wicking clothing. [ABSTRACT FROM AUTHOR]

Piezoelectric nanogenerators (PENGs) are promising for harvesting renewable and abundant mechanical energy with high efficiency. Up to now, published research studies have mainly focused on increasing the sensitivity and output of PENGs. The technical challenges in relation to practicability, comfort, and antibacterial performance, which are critically important for wearable applications, have not been well addressed. To overcome the limitations, we developed an all-nanofiber PENG (ANF-PENG) with a sandwich structure, in which the middle poly(vinylidene fluoride-co-hexafluoropropylene (P(VDF-HFP))/ZnO electrospun nanofibers serve as the piezoelectric layer, and the above and below electrostatic direct-writing P(VDF-HFP)/ZnO nanofiber membranes with a 110 nm Ag layer on one side that was plated by vacuum coating technique serve as the electrode layer. As the ANF-PENG only has 91 µm thick and does not need further encapsulating, it has a high air permeability of 24.97 mm/s. ZnO nanoparticles in ANF-PENG not only improve the piezoelectric output, but also have antibacterial function (over 98%). The multifunctional ANF-PENG demonstrates good sensitivity to human motion and can harvest mechanical energy, indicating great potential applications in flexible self-powered electronic wearables and body health monitoring. [ABSTRACT FROM AUTHOR]

The present work aims at improving the properties of waterproof breathable polyurethane membranes by introducing chemical crosslinks. A series of crosslinked polyurethanes were prepared by chain extension of prepolymer containing varying amounts of a triisocyanate‐based crosslinker (0–15% wt/wt). Thin polyurethane films (~40 μm) were prepared by a solution casting technique and the effect of introducing the crosslinker on thermal, mechanical characteristics was established. Crosslinking led to an increase in glass transition temperature. All crosslinked polyurethanes exhibited a sub‐ambient Tg. Both tensile and tear strengths were found to improve with crosslinking. Crosslinking (15% wt/wt) led to an increase in waterproofness from 112 ± 11 mbar to 574 ± 23 mbar, while the breathability reduced from 1246 ± 52 g/m2/day to 678 ± 32 g/m2/day. Polyurethane membranes containing 10% crosslinker exhibited an optimal balance of waterproofness and breathability, where the film was found to possess a water vapor transmission rate (WVTR) of 834 ± 37 g/m2/day with a hydrostatic pressure of 490 ± 18 mbar. This was subsequently coated on a cotton–polyester fabric to fabricate a breathable textile which was found to exhibit a WVTR of 663 ± 18 g/m2/day and a hydrostatic pressure of >3 bar, which was suitable for practical applications. [ABSTRACT FROM AUTHOR]

The World Health Organization and the United States Centers for Disease Control have recommended universal face masking by the general public to slow the spread of COVID-19. A number of recent studies have evaluated the filtration efficiency and pressure differential (an indicator of breathability) of various, widely available materials that the general public can use to make face masks at home. In this review, we summarize those studies to provide guidance for both the public to select the best materials for face masks and for future researchers to rigorously evaluate and report on mask material testing. Of the tested fabric materials and material combinations with adequate breathability, most single and multilayer combinations had a filtration efficiency of

Breathable films were prepared based on linear low-density polyethylene (LLDPE), calcium carbonate (CaCO3), and aluminum (Al; 0, 2, 4, and 8 wt.%) using extrusion molding at a pilot scale. These films must generally be able to transmit moist vapor through pores (breathability) while maintaining a barrier to liquids; this was accomplished using properly formulated composites containing spherical CaCO3 fillers. The presence of LLDPE and CaCO3 was confirmed by X-ray diffraction characterization. Fourier-transform infrared spectroscopy results revealed the formation of Al/LLDPE/CaCO3 composite films. The melting and crystallization behaviors of the Al/LLDPE/CaCO3 composite films were investigated using differential scanning calorimetry. Thermogravimetric analysis results show that the prepared composites exhibited high thermal stability up to 350 °C. Moreover, the results demonstrate that surface morphology and breathability were both influenced by the presence of various Al contents, and their mechanical properties improved with increasing Al concentration. In addition, the results show that the thermal insulation capacity of the films increased after the addition of Al. The composite with 8 wt.% Al showed the highest thermal insulation capacity (34.6%), indicating a new approach to transform composite films into novel advanced materials for use in the fields of wooden house wrapping, electronics, and packaging. [ABSTRACT FROM AUTHOR]

Novel cloth face masks to mitigate the spread of COVID-19 have been developed and tested for particle (0.1 μm in size) filtration efficiency, bacterial filtration efficiency, breathability, leakage, heart rate, and blood oxygen level, and then compared with the available N95 masks and surgical masks. It was found that this novel mask had better filtration efficiency than that of surgical masks and was very close to that of N95 masks. The breathability was also improved and was in the range of the designated levels for barrier face coverings. The flow visualization technique was utilized to study the leakage of the mask and it was found to have significantly lower leakage as compared to surgical masks. Heart rate and blood oxygen level tests were performed by wearing the mask during 10-minute walking sessions and it was found that wearing the mask did not adversely affect heart rate or blood oxygen levels or add any other strain on the wearer. It is believed that this novel face mask would reduce the spread of COVID-19 as well as provide an environmentally and economically conscious alternative to the N95 respirators for the public. The mask developed in this study can be washed, reused, and therefore worn for longer periods of time. [ABSTRACT FROM AUTHOR]

The article presents an analysis of the results of a study of the physical and mechanical properties of packages of materials of various compositions for soldiers' uniforms. The relevance of the article is as follows: currently, one of the urgent problems is the inconsistency of uniforms with consumer requirements, the insufficiency of domestic, high-quality, affordable uniforms for military personnel, the lack of research in Kazakhstan on the production of thermal insulation, including non-woven materials. The production of nonwovens occupies a special place among the branches of the textile industry, since the specific properties of these materials allow not only their widespread use as substitutes for fabrics, knitwear, but also to create canvases with fundamentally new properties. Therefore, non-woven materials from domestic raw materials were presented as thermal insulation materials when processing products for soldiers. The purpose of the article is to study the properties of a package of materials for designing uniforms for military personnel. A feature of using the proposed technology in the development of several variants of a new material for the widespread use of domestic raw materials is the production of non-woven material based on a combination of camel and sheep wool by needle method. Experimental researches of the properties of nonwoven insulation materials were carried out using standard methods in laboratory conditions.

Wearable electronic skins have aroused extensive interest in health detection, human–computer interaction, and robotics. However, it remains a great challenge to realize the multifunctional electronic skin with a wide detection range, high sensitivity, multi‐stimulus response, and wearable comfort on a single device. Here, a flexible porous thermoplastic polyurethane (TPU)/carbon black (CB) multimodal sensor that perceives multiple stimuli of pressure, strain, and humidity is prepared by the water vapor‐induced phase separation method. The as‐prepared device exhibits a wide pressure detection range (up to 49 kPa), excellent sensitivity (0.21 kPa−1), fast response (150 ms), and recovery time (120 ms). Furthermore, as a strain sensor, it is not only highly stretchable (730%), but also can operate over a strain range of 0–240% with a sensitivity of up to 1485.2 and excellent durability. Moreover, the designed sensor can detect humidity changes from 35% to 90% and has a fast response time (1.2 s), while enabling non‐contact sensing of a fingertip. Importantly, the porous TPU/CB film presents excellent breathability, enabling it to achieve a high level of comfort. Therefore, the perfect integration of these features ensures the potential applications of porous TPU/CB sensors in human activity detection, exhale monitoring, and breathable wearable devices. [ABSTRACT FROM AUTHOR]

The successful implementation of bioelectronic devices attached to living organism hinges on a number of material and device characteristics, including not only electrical and mechanical performances to gather physiological signals from living organism thus enabling status monitoring, but also permeability or breathability for gas/nutrient exchange between living organisms and surroundings to ensure minimum perturbation of the intrinsic biological function. However, most bioelectronic devices built on planar polymeric substrates, such as polydimethylsiloxane (PDMS), polyurethane (PU), and polyimide (PI), lack efficient gas permeability, which may hinder the emission of volatile compounds from the surface of living organism, affecting the natural metabolism and reducing the comfort of wearing. Thus, achieving permeability or breathability in bioelectronic devices is a significant challenge. Currently, the devices made of gas-permeable materials with porous structures, that combine electronic components with daily garments, such as fibric and textile, offer exciting opportunities for breathable electronics. In this review, several types of gas-permeable materials with their synthesis and processing routes are outlines. Then, two methods for measuring water vapor transmission rate of materials are discussed in depth. Finally, recent progress in the use of gas-permeable materials for the applications of plant- and skin-attached electronics is summarized systematically. [ABSTRACT FROM AUTHOR]

Face masks have an effect of preventing the spread of infectious diseases such as coronavirus disease 2019 (COVID-19). With these masks, it is primarily aimed to prevent the environment from being contaminated by the user. However, in the COVID-19 outbreak, many countries made it mandatory to use masks in areas with high human circulation such as marketplaces, shopping malls and hospitals, and then in all areas outside the home. Some tests such as filtration efficiency, microbial load, resistance to body fluids, flammability and breathability are performed to determine the protection potential and wearing comfort of face masks. In this study, we investigated the bacterial filtration efficiency (%), microbial load (cfu/g), breathability (Pa/cm2) and air permeability values of five different face masks obtained by combining polypropylene (PP) nonwoven layers in different weights (accordance with EN 14683:2019 + AC:2019, EN ISO 11737-1:2018 and TS 391 EN ISO 9237 Standards). The surface morphologies of the nonwoven fabrics were characterized by scanning electron microscope (SEM). It was observed that the weight change in spunbond masks (1–4) was directly proportional to bacterial filtration efficiency and differential pressure, and inversely proportional to air permeability. In addition, SEM analysis showed that the average fiber diameter of the meltblown layer was at least 5.80 times smaller than the spunbond layers, and as a result, dramatic differences were also observed in the air permeability and differential pressure values of the Spunbond-Meltblown-Spunbond (SMS) mask (5) compared to spunbond masks. [ABSTRACT FROM AUTHOR]

A notable application of polymeric nanocomposites is the design of water vapor permeable (WVP) membranes. “Breathable” membranes can be created by the incorporation of micro/nanofillers, such as CaCO3, that interrupt the continuity of the polymeric phase and when subjected to additional uniaxial or biaxial stretching this process leads to the formation of micro/nanoporous structures. Among the candidate nanofillers, carbon nanotubes (CNTs) have demonstrated excellent intrinsic WVP properties. In this study, chemically modified MWCNTs with oligo olefin-type groups (MWCNT-g-PP) are incorporated by melt processes into a PP matrix; a β-nucleating agent (β-ΝA) is also added. The crystallization behavior of the nanocomposite films is evaluated by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The WVP performance of the films is assessed via the “wet” cup method. The nanohybrid systems, incorporating both MWCNT-g-PP and β-NA, exhibit enhanced WVP compared to films containing only MWCNT-g-PP or β-NA. This improvement can be attributed to the significant increase in the growth of α-type crystals taking place at the edges of the CNTs. This increased crystal growth exerts a form of stress on the metastable β-phase, thereby expanding the initial microporosity. In parallel, the coexistence of the inherently water vapor-permeable CNTs, further enhances the water vapor permeability reaching a specific water vapor transmission rate (Sp.WVTR) of 5500 μm.g/m2.day in the hybrid composite compared to 1000 μm.g/m2.day in neat PP. Notably, the functionalized MWCNT-g-PP used as nanofiller in the preparation of the “breathable” PP films demonstrated no noteworthy cytotoxicity levels within the low concentration range used, an important factor in terms of sustainability.

Abstract Wearable electronic skins have aroused extensive interest in health detection, human–computer interaction, and robotics. However, it remains a great challenge to realize the multifunctional electronic skin with a wide detection range, high sensitivity, multi‐stimulus response, and wearable comfort on a single device. Here, a flexible porous thermoplastic polyurethane (TPU)/carbon black (CB) multimodal sensor that perceives multiple stimuli of pressure, strain, and humidity is prepared by the water vapor‐induced phase separation method. The as‐prepared device exhibits a wide pressure detection range (up to 49 kPa), excellent sensitivity (0.21 kPa−1), fast response (150 ms), and recovery time (120 ms). Furthermore, as a strain sensor, it is not only highly stretchable (730%), but also can operate over a strain range of 0–240% with a sensitivity of up to 1485.2 and excellent durability. Moreover, the designed sensor can detect humidity changes from 35% to 90% and has a fast response time (1.2 s), while enabling non‐contact sensing of a fingertip. Importantly, the porous TPU/CB film presents excellent breathability, enabling it to achieve a high level of comfort. Therefore, the perfect integration of these features ensures the potential applications of porous TPU/CB sensors in human activity detection, exhale monitoring, and breathable wearable devices.

The permeability of fiber-based materials and general medical textiles is very important, and it is commonly believed that air permeability and water permeability are correlated. This property is expressed as the breathability of the material. Knowing the air permeability is helpful in predicting the water vapour permeability as well, but whether this really works for textiles at different pressures and humidities still needs to be explored. In this study, this hypothesis is examined, and it is discovered that this phenomenon does not show significant corelation. Moreover, the non-standardised unit of measurement of breathability makes the comparison much more complex in terms of textiles. The articles focuses on any possible relationship between the air and water vapour permeability of textiles. [ABSTRACT FROM AUTHOR]

Development of ecofriendly packaging materials is still a challenging area. Researchers are continuously working to improve the mechanical and barrier properties of the different polymers which are used in the packaging industry. Selection of reinforcement and matrix for any composite are based upon end use applications. The novelty of the work is development of fully biodegradable, flexible, lightweight biocomposite by reinforcing needle punched flexible nonwoven viscose fabric to the PVA solution. The effect of PVA concentration and areal density of viscose fabric on the properties of prepared composite is examined. The composite thus prepared is assessed in terms of mechanical, thermal, breathability, and UV blocking properties. The nonwoven viscose‐PVA composite shows excellent improvement in tensile strength of 100% to 300% with respect to PVA film of equivalent concentration for two different areal densities of viscose fabric. The composite also exhibits improved thermal stability and UV blocking property with respect to parent components. However, a reduction in flexibility (with respect to PVA film) as well as breathability (with respect to viscose fabric) of the composite is observed. Based upon the improved performance of the viscose‐PVA composite in terms of mechanical properties, UV and water vapor permeability, it seems that the composite has a strong potential for application in the packaging sector as a flexible as well as biodegradable composite. [ABSTRACT FROM AUTHOR]

In this study, cellulose nanocrystals hollow microspheres (HMs) were fabricated through Pickering emulsion polymerization, in which hydrophobically modified cellulose nanocrystals (CNCs) acted as Pickering stabilizers. The hollow interior core was prepared by solvent evaporation. This manuscript describes the synthesis of HMs in detail. The hollow structure and nanoscale size of HMs were verified using TEM. The resultant HMs could easily coat self-forming films on the surface of PET fabrics. Additionally, these coatings exhibited superior breathability and moisture permeability properties with a high one-way transport index of 936.33% and a desirable overall moisture management capability of 0.72. Cellulose nanocrystal hollow microsphere coatings could be used as a moisture-wicking functionality agent for finishing fabrics, oil–water separation, and fog harvesting. [ABSTRACT FROM AUTHOR]

Speak-Easy© prototype masks came from efforts to assist in the communication process for individuals with hearing limitations or individuals whose jobs that require seeing lip movement. Masks can muffle speech and make communication more difficult. The Functional, Expressive, and Aesthetic (FEA) Consumer Needs model provided the conceptual framework for the study. This project provided hands-on experience for student and faculty collaborative to address consumers' needs. For the project, two Speak-Easy© prototype mask variations were designed and constructed. The Speak-Easy© I design goal was to provide ease of seeing lip movement and a basic pattern for individuals with sewing skills. The Speak-Easy© I mask performed within end-user expectations and needs and outperformed many non-medical fabric masks tested for FE and dP. The Speak-Easy© II prototype mask was designed to stand away from the wearer's face, to be comfortable throughout the workday, and provide a fog-free transparent window for ease of lip-reading. [ABSTRACT FROM AUTHOR]

Electronic skin (E‐skin) is widely used in bionic prosthesis, soft robotics, and wearable electronic devices. Waterproof and breathable membranes that provide a high level of protection and comfort are promising core materials for meeting the pressing demand for E‐skin. However, creating such materials exhibiting waterproofness, breathability, and ease of fabrication has proven to be a great challenge. In this paper, waterproof, breathable Modal‐based knitted fabric E‐skin is proposed by using a simple, low‐cost three‐step process including the graphene oxide (GO) loading, GO‐reducing, and polydimethylsiloxane loading. The prepared E‐skin is insensitive to common liquids in daily life including water, tea, milk, and coffee, showing superior waterproof capability. The breathability is also tested with a water vapor transmission rate of ≈13.6 mg cm−2 h−1. Besides, this E‐skin can achieve reliable human motion monitoring. The authors believe this E‐skin can provide a reliable principle for further design and development of waterproof and breathable electronic skin. [ABSTRACT FROM AUTHOR]

[Display omitted] • A micro-protective coating was applied to the multi-scale microstructure of wood. • The porous structure of wood is preserved, maintaining its permeability. • Multi-scale micro-coatings provide wood with excellent fire safety properties. • Wood gains antibacterial, photoaging-resistant, and corrosion-resistant properties. • This strategy has been proven reliable, versatile, and durable for various metals. Wood, a naturally renewable material with a porous structure and breathability, rendering it a green construction material that can absorb sound, isolate heat and regulate moisture. Efforts to enhance wood's resistance to combustion while maintaining its porous nature are hindered by the potential impact of physical and chemical treatments on its porous structure, posing a challenge in achieving flame-retardant wood that retains its breathability. Inspired by the multi-layer coating decoration method used on walls of various rooms in frame structure buildings, the study applies multi-scale micro-coating strategy to the multi-scale microstructure of wood. This strategy applied polyamino polyether methylene phosphonate (PAP), metal ions (Al3+/ Mg2+/ Ca2+), and alkali solutions to create a persistent multifunctional protective coating for the multi-scale wood structure. This coating effectively preserved the wood's vessel, ray tissue, cell cavity, and pit structure, protecting its permeability. The modified wood demonstrated an increased limited oxygen value from 19.7 % to 38.4 % and a 55.9 % decrease in the total smoke release compared to natural wood, obtaining high fire safety. Furthermore, the modified wood exhibited adjustable antibacterial, photoaging-resistant and corrosion resistance properties depends on the type of metal. This strategy demonstrated proven reliability, versatility, and durability in the treatment of various metal ions, enabling the production of functional wood with tailored properties. [ABSTRACT FROM AUTHOR]

Water transport through membranes is an attractive topic among the research dedicated to dehydration processes, microenvironment regulation, or more simply, recovery of freshwater. Herein, an atomistic computer simulation is proposed to provide new insights about a water vapor transport mechanism through PEBAX membranes filled with ionic liquid (IL) [C12C1im]Cl. Starting from experimental evidence that indicates an effective increase in water permeation as the IL is added to the polymer matrix (e.g., up to 85·10−3 (g·m)/(m2·day) at 318.15 K for PEBAX@2533 membranes loaded with 70% of IL), molecular dynamics simulations are proposed to explore the key role of IL in water transport inside membranes. The polar region composed of anions and cationic head groups of the IL is demonstrated to serve as the pathway for water transport through the membrane. Water molecules always stay near the pathway, which becomes wider and thus has a larger water-accessible area with increasing IL concentration. Hence, the diffusion coefficients of water molecules and ions increase as the IL concentration increases. The simulation provides useful indications about a microscopic mechanism that regulates the transport of water vapor through a kind of PEBAX/IL membrane, resulting in full agreement with the experimental evidence.