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The coronavirus disease of 2019 (COVID-19) has become a global pandemic, leading to severe health issues such as pneumonia, organ failure, and death. Face masks made of non-woven textiles have been widely used to protect against SARS-CoV-2, but concerns arose regarding the potential infection from contaminated masks. To address this, titanium dioxide, a photocatalyst, shows promise in antimicrobial applications, including virus inhibition. This study explores the development of a sheath-core bicomponent fibre with a polypropylene core and a sheath containing an Ag and Zr co-doped TiO2 photocatalyst (AZT). Zr-Ag-TiO2 The fibres were produced using a double-extrusion spinning system, and the effects of the sheath-core ratio (50:50 and 80:20 w/w) and AZT content (1-3 wt%) on mechanical and antiviral properties were analysed. The fibres demonstrated improved mechanical strength and thermal stability, with the highest anti-SARS-CoV-2 activity (99.91%) observed in fibres with 2 wt% AZT at a 50:50 ratio after 30 min of fluorescent irradiation. [ABSTRACT FROM AUTHOR]

In order to investigate the influence of a hot-pressing process on the mechanical properties of ultra-high molecular weight polyethylene (UHMWPE) fiber non-woven fabrics with stretch and in-plane shear, UHMWPE non-woven fabric samples were prepared by adjusting the temperature, time, and pressure of the hot-pressing process, and mechanical property tests were carried out so as to clarify the influence of the hot-pressing process on the mechanical properties of the samples. The results show that the hot-pressing process mainly affects the silk–glue bonding strength of the samples; in the test range, with the increase in hot-pressing temperature and time, the tensile strength and in-plane shear strength of the samples increase and then decrease, and the best mechanical properties are obtained at 130 °C and 7 min of hot pressing, respectively; at 130 °C, the in-plane shear strength is 39.94 MPa and the tensile strength is 595.43 MPa; at 7 min, the in-plane shear strength is 63.0 MPa and the tensile strength is 643.30 MPa; with the increase in the hot-pressing pressure, the in-plane shear strength of the samples increases and then decreases, and the highest is 52.60 MPa, achieved at 8 MPa; in the range of 5–8 MPa, the tensile strength of the specimens did not change significantly, and increased significantly at 9 MPa, reaching a maximum strength of 674.55 MPa. [ABSTRACT FROM AUTHOR]

Abstract Multifunctional flexible conductive materials have generated significant interest in developing future portable electronic systems, including wearable electronics, implantable devices, and many more. Producing wearable electronics materials that are dependable in all-weather situations and provide high-performance electromagnetic interference (EMI) shielding remains challenging. "electromagnetic textile materials" refers to these wearable EMI shielding garments. One key material that can address the EMI problem facing systems such as wearable/flexible circuit working environments and human health is conductive polymeric nonwoven (NW) textile materials. In this review, our focus is primarily limited to the polymeric NW textile and their composites family as effective EMI shielding materials. The study provides the fundamentals of NW-based EMI shielding mechanisms, mechanisms to mitigate EM reflection, and fabrication techniques of EMI shielding NW materials. Also, the standard for future researchers to select the ideal material combination for effectively mitigating EMI waves as shields/filters is presented. Review articles exist on EMI shielding textiles in general, but no single article is dedicated to NW textile-based EMI shields. Again, no review article exists presenting the approaches employed towards mitigating EM wave reflection in NW -based EMI shield design and fabrication. In addition, the challenges encountered with the fabrication and/or application of NW-based EMI shielding materials are presented in this paper. The question of why NW selection is the primary structure for EMI shield fabrication is presented herewith for the first time in this article.

Magnetorheological fluid (MRF) porous fabric composite has been demonstrated to improve the shear properties of MRF. Non-woven fabric is manufactured from a multitude of fibers through spinning or melt-blown processing methods. As the fundamental unit of non-woven fabric, fibers without spinning or melt-blown directly influence the shear properties of magnetorheological (MR) materials. However, the effect of unprocessed fiber on the shear properties of MR grease remains uncertain. This study introduces a novel MR grease with fiber threads (MRG-FT) by incorporating fiber threads into MRG. The effects of fiber thread length, mass fraction, and material type on MRG shear stress are investigated. Compared to conventional MRG, the maximum shear stress of MRG-FT is increased by 31.8% under the magnetic field of 0.64 T. A novel Herschel–Bulkley–Fiber (H-B-F) model that considers fiber parameters (tenacity, mass fraction, etc.) is proposed based on the H–B model. To validate the enhancement of MRG by fiber threads, a linear damper based on shear mode has been designed and tested. The results demonstrate a 23.8% increase in the maximum damping force of MRG-FT compared to conventional MRG under an excitation current of 1.6 A. This study reveals the influence of fiber threads, which directly influences the shear properties of MRG upon the application of the magnetic field. The maximum damping force of the MRG can be increased by 23.8% by only 1.5% mass fraction of fibers. [ABSTRACT FROM AUTHOR]

Disposable surgical gowns are usually made from petroleum-based synthetic fibers that do not naturally decompose, impacting the environment. A promising approach to diminish the environmental impact of disposable gowns involves utilizing natural fibers and/or bio-based synthetic fibers. In this study, composite webs from polylactic acid (PLA) bicomponent fiber and natural fibers, cattail and kapok fibers, were prepared using the hot press method. Only the sheath region of the PLA bicomponent fiber melted, acting as an adhesive that enhanced the strength and reduced the thickness of the composite web compared with its state before hot pressing. The mechanical and physical properties of these composite webs were evaluated. Composite webs created from kapok fibers displayed a creamy yellowish-white color, while those made from cattail fibers showed a light yellowish-brown color. Additionally, the addition of natural fibers endowed the composite webs with hydrophobic properties. The maximum natural fiber content, at a ratio of 30:70 (natural fiber to PLA fiber), can be incorporated while maintaining proper water vapor permeability and mechanical properties. This nonwoven material presents an alternative with the potential to replace petroleum-based surgical gowns. [ABSTRACT FROM AUTHOR]

The effects of treatment regimes on the mechanical properties of nonwoven needlepunch fabrics based on a blend of poly(ethylene terephthalate) fibers of linear density 0.33 and 1.7 tex and bicomponent fibers of 0.44 tex were studied. The stretching mechanism of various fabric compositions and the effect of adding fibers of higher linear density on structure formation and the mechanical properties of the fabrics were examined. The parameters for evaluating the stretching resistance, which occurred in two stages, were found. Materials with increased stretching resistance and unchanged tensile strength were obtained. [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.)

Nine 1/1 plain weave fabric samples were developed using various combinations of low-twist ring spun yarns and rovings of FR viscose, p-aramid, and their blends. The three woven combinations were yarn/yarn, yarn/roving, and roving/roving. These fabric samples were compared for mechanical and thermal properties with needle-punched non-woven fabric samples. The radiant heat transfer index (RHTI24) and convective heat transfer index (HTI24) of the woven and non-woven fabrics were determined. In all samples, the HTI24 - HTI12 and RHTI24 - RHTI12 values were more than 4 seconds, which suggested that there was enough time between experiencing pain and sustaining second-degree burns. [ABSTRACT FROM AUTHOR]

The development of a textile analysis protocol for natural fibers suggests that several natural species can be considered as textile raw materials for the production of different textile genres and they can be used within the clothing industry by appreciating the qualities they possess. Among the objectives is to determine the feasibility of using natural fibers in a textile genre and to do so, the physical and morphological characteristics of the natural fibers must be investigated as well as analyzed to finally develop the textile analysis protocol, which includes physical and morphological. The criteria of experts related to all fields of the textile industry were investigated through interviews, with the objective of determining what are the minimum characteristics necessary to obtain a textile fabric of the woven or non-woven type that is usable within the clothing industry, additionally The information collected was taken into account after developing a bibliographic analysis on national and international control standards. In the development of the tool for textile analysis, it was possible to establish a textile analysis protocol supported by control standards that provide the necessary information for the analysis of natural fibers. The analysis developed with this protocol is an indicator to determine if a material can be considered for the production of woven and non-woven textiles, with the experimentation of the production of textiles at an industrial level still pending. [ABSTRACT FROM AUTHOR]

Aimed to expand applications of aramid fiber fabrics and provide a reference for select fibers for filter bags using in high temperature flue gas filtration, properties such as filtration performance, temperature resistance, wear resistance, folding endurance, corrosion resistance and flame retardance of aramid fibre needle punched nonwoven fabrics were measured, in comparison with polyimide fiber needle punched nonwoven fabrics and glass fiber woven fabrics. It is found that aramid fiber fabric exhibits excellent temperature resistance. The tensile strength remains unchanged after thermal treatment under 220 °C for 24 hours. The folding endurance and corrosion resistance are excellent. The filtration performance of fabrics composited with 1 D aramid fibers is excellent while its flame retardance and wear resistance should be improved by PTFE emulsion impregnation. [ABSTRACT FROM AUTHOR]

The accumulation of heat in electronic devices puts forward an urgent demand for thermal interface materials. It is still a great challenge to achieve the good comprehensive performance of high thermal conductivity (TC), insulation, flexibility and tensile strength. In this work, polyester‐based nonwoven fabric (NWF) was coated with boron nitride nanosheets (BNNS) by dispersion and interfacial reinforcement of cellulose nanofibers to obtain a three‐dimensional thermally conductive network skeleton (BNNS@NWF). The sandwich‐structured composite film was assembled by introducing alumina (Al2O3)/polydimethylsiloxane (PDMS) layers on the top and bottom surfaces of BNNS@NWF using scratch coating and hot pressing processes. The composite film has a high TC of 6.42 W/mK at 45.8 wt% BNNS content, and has excellent insulation with a volume resistivity of 1.06 × 1015 Ω cm. This is due to the long‐range effective thermal conduction path constructed by BNNS, the bridging effect of Al2O3 and the synergistic effect of the two fillers. PDMS helps the composite film maintain good flexibility and good TC stability after 30 bending cycles. The PET nonwoven interlayer gives the composite film good mechanical properties with a tensile strength of 17.5 MPa. This work provides a strategy for the efficient preparation of flexible composite films with high TC and insulation properties, which is of great importance for the development of innovative thermal interface materials. Highlights: A sandwich‐structured composite film was prepared by a simple scale‐up method.Al2O3 and BNNS achieves synergistic enhancement of thermal conductivity.The film has a high thermal conductivity of 6.42 W/mK and electrical insulation.The film shows good flexibility, high tensile and thermal management properties. [ABSTRACT FROM AUTHOR]

The structure and properties of technical nonwoven fabrics based on polyester fibers, including those modified with heat-resistant compounds, were studied. Secondary fibers of various manufacturers, which differed in structure and properties, were chosen for the study. The main properties of the fibers and nonwoven materials therefrom were studied. Nonwoven materials of different structures were obtained by needle-punching, thermal bonding, and combined methods. Nonwoven materials with increased refractory properties were obtained by modification of polyester fibers with compounds based on easily available nontoxic fire retardants and with optimum technological parameters. [ABSTRACT FROM AUTHOR]

While nonwoven fabrics have existed for several decades, their usage in personal protective equipment (PPE) has been met with a rapid surge of demands, in part due to the recent COVID-19 pandemic. This review aims to critically examine the current state of nonwoven PPE fabrics by exploring (i) the material constituents and processing steps to produce fibers and bond them, and (ii) how each fabric layer is integrated into a textile, and how the assembled textiles are used as PPE. Firstly, filament fibers are manufactured via dry, wet, and polymer-laid fiber spinning methods. Then the fibers are bonded via chemical, thermal, and mechanical means. Emergent nonwoven processes such as electrospinning and centrifugal spinning to produce unique ultrafine nanofibers are discussed. Nonwoven PPE applications are categorized as filters, medical usage, and protective garments. The role of each nonwoven layer, its role, and textile integration are discussed. Finally, the challenges stemming from the single-use nature of nonwoven PPEs are discussed, especially in the context of growing concerns over sustainability. Then, emerging solutions to address sustainability issues with material and processing innovations are explored. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher 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.)

This paper reports an investigatory study on the structure and properties of nonwoven fabrics made from different fibre fineness. The structure of the nonwoven fabrics was analysed using the Image analysis technique and Lindsley's technique. Pore channel tortuosity was also calculated to quantify the porous path formed in the fibrous media. A relationship is developed between the structure and property of the nonwoven fabrics which helps in designing a suitable nonwoven filter media. In the later part, an attempt is made to regulate the structure by layering the batts made from different linear densities of fibres in various combinations to improve the filtration performance. It was interestingly established that an inverse gradient structure of batts having decreasing order of fibre orientation in the layered structure provided the lowest pressure drop along with near highest filtration efficiency. This study provides an insight into modulating the structure of the layered nonwoven fabric using different linear density fibres to prolong the life of the filter media. [ABSTRACT FROM AUTHOR]

Graphene fibers non-woven fabrics (GFFs) are a new type of carbon-based fabrics formed by the overlapping and fusion of graphene fibers, which have good structural stability, flexibility and excellent electrical and thermal properties. However, the pure GFFs are usually poor electrocatalytic without fire-retardant properties due to the dense structure of graphene fibers and few functional groups on the graphene sheet. Here we report a N, P co-doped GFFs (N, P-GFFs) prepared by wet-fusing assembly graphene oxide fibers containing hexachlorocyclotriphosphazene (HCTP) and pyrolysis of the mixture. The introduction of N and P atoms increases the active sites of GFFs, which significantly enhances its electrocatalytic activity, and also makes GFFs with high flame-retardant performance. The newly developed multifunctional refractory nonwoven fabrics are promising great potential in real-world applications. [ABSTRACT FROM AUTHOR]

Fibre spreading before impregnation process has great importance for production of non-woven fabrics. Thousands of filaments can be transported and spread by airflow in a pneumatic chamber. To better understand the lateral-spreading mechanism of the system, the generation and evolution of lateral dragging forces applied on fibre bundle are demonstrated through experiments and simulations. with the CFD model of the spreader and discrete element method (DEM), the spreading behavior of the filaments in the bundle are simulated. By parametrically analyzing the characteristics of fractal airflows, the influence of design parameters on the fractal airflow is analyzed and optimized. The simulation results are in good agreement with the experimental data. The width of the bundle has been widened almost 10 times, which has improved by 100 % compared with traditional mechanical spread method. [ABSTRACT FROM AUTHOR]

Conventional personal protective equipment is usually made in multilayer stacks, and appears clumsy and uncomfortable, offering limited protection. In recent years, a newly-developed nanosuspension, shear thickening fluids (STFs), has been commonly applied to buffer and shock absorption. In this study, nonwoven fabrics are impregnated with 30 wt%, 35 wt%, or 40 wt% STF in order to strengthen the interaction among fibers. The resultant STF composite nonwoven fabrics are observed for their morphology, and tested for their tensile strength, tearing strength, bursting strength, and dynamic impact resistance, thereby examining the damage resistance of the materials. The SEM images indicate that the fibers are adhered with a tremendous amount of silicon dioxide (SiO2) particulates with a rise in the STF concentration, due to which the smooth fibers become rough. Moreover, the mechanical test results indicate that a rise in the STF concentration improves the frictional force during the relative motion of fibers, which subsequently mechanically strengthens the STF composite nonwoven fabrics. The dynamic impact test results show that when the STF concentration increases from 30 wt% to 35 wt%, the materials exhibit dynamic impact strength that is significantly improved to 51.9%. Nonetheless, significant improvement in dynamic impact strength is absent when the STF concentration increases to 40 wt%. To sum up, a critical value of STF concentration has a positive influence over the mechanical strengths of STF composite nonwoven fabrics. [ABSTRACT FROM AUTHOR]

The effect of the technology of roll calender processing of nonwoven needle-punched fabric based on a blend of polymer and bicomponent fibers on the correlation between the decrease of porosity and the tensile strength of the processed materials is investigated. The characteristics of fabric processing on roll calender are studied. A method is proposed for loading the calender, in which the time of contact of the fabric with the heated rollers increases. The porosity of the fabric decreases steadily with decrease of the gap between the rollers, whereupon the tensile strength of the material reaches the maximum at a particular gap between the rollers. [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.)

Fibrous construction and combination of different fine/coarse fibres, bonding techniques and the directional arrangement of fibres are the significant performance parameters of the unique characteristics in nonwovens and their composites applications in filtration products. After the ceramic/glass fibre needle-punched nonwoven characterisation, the diagonal stitch bonding made with PTFE-coated glass yarn on the nonwoven which influenced more on the tensile properties increased by 1.91–2.36 times than their initial strength and this is mainly due to the glass yarn which supporting the nonwoven fabric reducing the glass fibre slippage. The bursting strength significantly increased in a range of 1.4–1.6 times comparatively lower than tensile strength improvement where this minimal increase due to testing sample parameters where the glass fibre length itself supported the bursting strength 40 mm diaphragms. Further, to improve the tensile properties of the optimised samples, they were stitch bonded with 200 Denier glass fibre yarn diagonally at 10 mm intervals and analysed for their tensile behaviours as well as their physical and filtration characteristics. [ABSTRACT FROM AUTHOR]

In order to obtain sanitary spunbond nonwovens with excellent softness and air permeability, the fiber type, fiber fineness and areal density of the spunbond fabric were controlled by changing the polymer raw materials and process parameters, and the fibers with different fiber fineness and areal density were prepared. The effect of areal density on the properties of two spunbond nonwovens was studied, and the differences in the properties of the two spunbond fabrics with the same areal density were compared. The results show that the breaking strength, elongation at break and thickness of spunbond nonwovens increase with the increase of areal density, while the coefficient of variation, air permeability and softness decrease with the increase of areal density. Under the same areal density, the thickness, elongation at break, softness and air permeability of PE/PP bicomponent spunbond nonwovens are all greater than those of PP spunbond nonwovens, while the breaking strength decreases slightly. The low areal density (15 g/m²) PE/PP bicomponent spunbond non-woven fabric has a fiber fineness of 21.6 µm, a bending length of 1.28 cm, and an air permeability of 6 995.1 mm/s. Its softness and air permeability are significantly improved, and it can be used as a covering material for disposable sanitary products. [ABSTRACT FROM AUTHOR]

Translating the superlative mechanical properties of nanocarbons to the scale of structural components requires assembling them into highly aligned networks with uniform internal stress transfer. Continuous, non-woven fabrics are produced by winding multiple filaments of carbon nanotube fibres (CNTF) directly spun from the gas phase. The CNTF fabrics are drawn by stretching in regular solvents, which increases specific tensile strength to 1.2 GPa/SG and modulus to 44 GPa/SG, reaching ∼70% the strength and ∼50% modulus of the single filament. Tensile measurements of misaligned CNTF fabrics soaked in solvents show an increased strain-to-break, a large drop in tensile force, and shear-induced local deformation, analogous to a polymer wet-drawing process. In-situ small-angle X-ray scattering during wet-drawing shows a progressive and transient increase in porosity, attributed to the separation of adjacent bundles "wedged" by the ingress of solvent when the fabric is under load. Wet-drawing increases degree of alignment, reaching Herman's orientation parameter values = 0.54 and a narrower distribution of local alignment. Maps of the downshift of 2D Raman band during tensile deformation confirm a more homogeneous spatial distribution of local moduli after wet-drawing CNTF fabrics, evidencing more cooperative loading and stress transfer. Tensile mechanical properties of fabrics aligned after wet-drawing can be successfully described by the uniform stress transfer model. [Display omitted] • in situ small-angle X-ray and Raman analysis of carbon nanotube fibre fabrics. • Wet-state drawing improves degree of alignment and cooperative loading in fabrics. • Wet-drawn fabrics reach ∼70% the strength and ∼50% modulus of the single filament. • Tensile properties of fabrics are described by the uniform stress transfer model. [ABSTRACT FROM AUTHOR]

The present work aimed to investigate the effect of nanofiber enhancement on the sound absorption performance of fibrous materials through a brief review of the recent progress in the field and highlight the current challenges and issues for measuring and modeling the sound absorption coefficient (SAC) of such structures. Moreover, some composite samples consist of polyethylenterephthalat (PET) nonwoven fabric and polyacrylonitrile (PAN) nanofibers web were prepared to be studied as a case study. The nanofiber deposition amounts, nanofiber orientation, and nanofiber layering sequence were chosen as the main variables of samples. Various amounts of deposition were achieved through three different electrospinning (ES) time of 15, 60, and 180 min. The random and aligned orientation of the nanofiber web was obtained by using a rotating collector. The effect of the layering sequence of the nanofiber layer was studied in the form of quadruple-layered assemblies of samples. The results showed that the samples incorporated with the nanofiber layer with 60 min of ES and random orientation when it is used in the second position of the layering sequence have the best performance of sound absorption, mainly at lower critical frequency range. Furthermore, a discussion on some available empirical models and compare the results confirms that there is a need for developing a new approach for measuring and modeling the SAC and consequently designing such absorbers. [ABSTRACT FROM AUTHOR]

Functional fabrics with antibacterial performance are more welcome nowadays. However, the fabrication of functional fabrics with durable, steady performance via a cost-effective way remains a challenge. Polypropylene (denoted as PP) nonwoven fabric was modified by polyvinyl alcohol (denoted as PVA), followed by the in-situ deposition of silver nanoparticles (denoted as Ag NPs) to afford PVA-modified and Ag NPs-loaded PP (denoted as Ag/PVA/PP) fabric. The encapsulation of PP fiber by PVA coating contributes to greatly enhancing the adhesion of the loaded Ag NPs to the PP fiber, and the Ag/PVA/PP nonwoven fabrics exhibit significantly improved mechanical properties as well as excellent antibacterial activity against Escherichia coli (coded as E. coli). Typically, the Ag/PVA/PP nonwoven fabric obtained at a silver ammonia concentration of 30 mM has the best mechanical properties and the antibacterial rate reaches 99.99% against E. coli. The fabric retains excellent antibacterial activity even after washing for 40 cycles, showing prospects in reuse. Moreover, the Ag/PVA/PP nonwoven fabric could find promising application in industry, thanks to its desired air-permeability and moisture-permeability. In addition, we developed a roll-to-roll production process and conducted preliminary exploration to verify the feasibility of this method. [ABSTRACT FROM AUTHOR]

Down fiber is one of the most superior materials, with excellent thermal properties, that can be used in bedding, clothing, and so on. Down products are usually encapsulated in fabrics that are more compact and, therefore, impart an anti-drilling performance. In this study, down fibers were encapsulated in polypropylene melt-blown nonwoven fabric, and also in polyester woven cloth, to form two different kinds of composite waddings. The waddings made of down fiber encapsulated in melt-blown nonwoven fabrics have a superior moisture permeability, thermal insulation, and anti-drilling performance, and a slightly inferior air permeability compared to that of waddings made with traditional woven fabrics. The pore fractal dimensions of melt-blown nonwoven fabrics are larger than that of woven fabrics. The relationship between the fractal dimension and performance of waddings explains the difference. [ABSTRACT FROM AUTHOR]

Compared to the commonly used synthetic fibrous materials, natural fiber represents an eco-friendly solution in various engineering fields. Noise control is an important application of natural fibers due to the unique acoustic characteristics. Studies on the sound absorption of hemp fibers have attracted more and more attention in recent years. Generally, hemp products for sound absorption mainly including nonwoven fabrics and fiber-reinforced composites. This review has gathered the most recent advances on the acoustics of hemp fibers, and also the sound absorption design principles of hemp-based materials. A detailed information related to the improvement of the sound absorption properties of hemp is given, which mainly including the optimization of manufacturing, materials component, bulk density, morphologies, and structural parameters, etc. Hemp fibers exhibit robust acoustical performance, and the present work is beneficial to the development of sound absorption hemp-based materials. [ABSTRACT FROM AUTHOR]

In order to improve the construction efficiency of sand bag sloping breakwater in waterway regulation project, innovations were put forward around the key processes of material selection, design and processing. 510 g/m2 polypropylene filament woven fabric and 150 g/m2 non-woven fabric were used for the preparation of composite sand bag. The structure design of new sand bag was optimized through multi-layer disordered texture and unique weaving mode. The strength, permeability and sand retention of the new sand bag were verified through field test, and the breakthrough of sand bag filling height above 2 m was realized. Finally, the applicability and superiority of the new sand bag were proved in the first phase of the Yangtze estuary south channel regulation project. [ABSTRACT FROM AUTHOR]

In this study, sandwich nonwoven fabrics containing raw kapok and flax fibers were developed and produced on a needle-punching processing line for agrotextile/geotextile applications. A two-step approach has been devised to produce nonwovens with compatible mechanical performance. Different structural arrangements were tried, and the mechanical properties of the resulting sandwich fabrics characterized. The nonwoven structures integrating 100% raw kapok fiber layers showed superior mechanical performance, compatible with class III geotextiles. [ABSTRACT FROM AUTHOR]

The accurate determination of physical properties of filtration media is essential for predicting their performance for bag filtration use. The spatial distributions of fiber mass, air permeability, and thickness of three commercially available filtration media were evaluated and compared with the manufacturer's indicated values. The fiber mass and air permeability were distributed over a wide range, resulting in a large deviation from the indicated values. The filter efficiencies were measured for ten randomly sampled pieces from each filter, and the filter efficiency of the whole filtration media and particle emission rate were estimated. Even for filters with a fiber mass and air permeability close to the indicated values, their filter performances differed by approximately 15 %. [ABSTRACT FROM AUTHOR]

The jute fibers have been mechanically fibrillated, and the wet-laid nonwoven fabrics have been manufactured using these fibers at two different concentrations of binder. The mechanically fibrillated states from non-fibrillated and partially fibrillated to highly fibrillated are considered at different lengths of fibers such as 5 and 10 mm to 15 mm. The tensile strength, air permeability, and the acoustic property of formed web are analyzed. There is no significant effect of fiber fibrillation found on the tensile properties of the manufactured wet-laid web, while there is an effect of fiber fibrillation observed on air permeability. [ABSTRACT FROM AUTHOR]

With the increasingly serious air pollution, it is urgent to build a good indoor environment. How to improve performance of filter fiber materials has become the mainstream approach. In this article, the structure and filtration performances of nonwoven filter fibers before and after impregnation with carbon black were tested and analyzed. The results showed that a carbon black coating layer was wrapped on the surfaces of the changed nonwoven fabric filter fibers. The porosity of fibers decreased from 97.81% to 95.35%. The filtration efficiency of PM1.0, PM2.5, and PM10 increased by 16.8%, 28.0%, and 11.7%, respectively, at the best filtration velocity of 0.8 m/s. The filtration efficiency of PM2.5 had the most significant improvement. But the resistance increased by 1.18 times at the same time. The matching between filtration efficiency and resistance should be considered in using. This study provides reference value for the synthesis and application of new filter materials. [ABSTRACT FROM AUTHOR]

The production of nonwoven fabric dedicated to the hygiene sector of industry is a dynamically developing market segment. Competition among manufacturers forces high performance in the economic production of nonwoven fabric with appropriate physical–mechanical parameters. One of the most important processes which guarantees that such characteristics may be obtained in the production of nonwoven fabrics, is the carding process. The article presents the modelling of the carding process on a modern, double-drum carder. The dynamics of the formation of nonwoven slivers was analysed, taking into account the homogeneity of the density of the fleece formed. In the description of carding dynamics, the mass balance of fibres was taken into account. Numerical simulations concerning the gradual increase in fibre accumulation, over time – and in relation to the fibre collection factor and the number of rollers in the worker–stripper systems – are presented. [ABSTRACT FROM AUTHOR]

The combination of appropriate materials and structural design can compensate for flaw of a single pattern, providing the products with better functionalities. In this study, the custom-made nonwoven fabric machine can unwrap the filament tows before needle punching stage. Sandwich composites are proposed, consisting of two nonwoven fabrics as surface layers and laminated loops of filaments as the core. The puncture resistance of the sandwich composites are examined in terms of weight of filament loops and needle-punching depth, examining their influences. The employment of filaments has a remarkable influence on the mechanical performance of the composites. GF4G has static puncture resistance, dynamic puncture resistance, and bursting strength that are 89%, 30%, 88% higher than those of GF1G; 332%, 127%, and 500% higher than those of 2G; and 671%, 400%, and 1260% higher than those of G. Using filaments to reinforce nonwoven fabrics only requires simple equipment and easy operation. Furthermore, based on the requirements of different final products, diverse filaments and multiple parameters can be combined, thereby providing the composites with efficient production, solid reinforcement, and broad applications. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) has a significant potential as a biodegradable polymer, but its high cost and slow biodegradability restrict its use in disposable products. This study establishes a novel route to accomplish both objectives by the addition of low‐cost soy fillers into PLA, which reduced material cost and increased the degradation rate of resulting soy‐PLA fibers. Due to partial thermal degradation of soy fillers at PLA melt temperature, they could be melt‐compounded into PLA up to 5 wt%. Fine continuous fibers (D ∼ 25‐50 μm) were successfully produced via melt spinning, and further melt‐consolidated into prototypical nonwovens. The tensile strength of soy‐PLA fibers containing soy reside and soy flour were 56 ± 9 and 44 ± 5 MPa, respectively. Although slightly lower than that of neat PLA fibers (74 ± 2 MPa), the fibers possessed adequate tenacity for use as nonwoven fabrics. Fiber modulus remained unaffected at about 2.5 GPa. The soy‐PLA fibers displayed a relatively rough exterior surface and provided a natural‐fiber feel. The overall degradation of soy‐PLA fibers was accelerated about 2‐fold in a basic medium due to the preferential dissolution of soy that led to increased surface area within the PLA matrix indicating their potential for use in biodegradable nonwovens. [ABSTRACT FROM AUTHOR]

The capillary pressure and liquid wicking in fibrous nonwoven materials depend on the structural arrangement of fibers in three dimensions, which is influenced by the method and conditions used to manufacture the material. By adapting the hydraulic radius mechanism and drag force theory, a model is established for predicting the directional capillary pressure in three-dimensional nonwoven materials. As a case study, equations to predict the velocity of liquid wicking in a one-dimensional wicking strip test for nonwovens having a three-dimensional fiber orientation distribution are given based on the newly established capillary pressure model. These models and equations are based on measurable structural parameters including the fiber orientation distribution, fiber diameter, and fabric porosity. [ABSTRACT FROM AUTHOR]

Many fibrous materials such as nonwovens are consolidated via compaction rolls in a so-called calendering process. Hot rolls compress the fiber assembly and cause fiber-to-fiber bonding resulting in a strong yet porous structure. In this paper, we describe an algorithm for generating three dimensional virtual fiberwebs and simulating the geometrical changes that happen to the structure during the calendering process. Fibers are assumed to be continuous filaments with square cross sections lying randomly in the x or y direction. The fibers are assumed to be flexible to allow bending over one another during the compression process. Lateral displacement is not allowed during the compaction process. The algorithm also does not allow the fibers to interpenetrate or elongate and so the mass of the fibers is conserved. Bending of the fibers is modeled either by considering a constant “slope of bending” or constant “span of bending.” The influence of the bending parameters on the propagation of compression through the material’s thickness is discussed. In agreement with our experimental observations, it was found that the average solid volume fraction profile across the thickness becomes U shaped after the calendering. The application of these virtual structures in studying transport phenomena in fibrous materials is also demonstrated. [ABSTRACT FROM AUTHOR]

A method for producing a material for filtering air mixtures consisting of nonwoven material combined with a form-stable mesh is proposed. The nonwoven fabric is made from Arselon fibres. [ABSTRACT FROM AUTHOR]

With the increasingly serious air pollution, it is urgent to build a good indoor environment. How to improve performance of filter fiber materials has become the mainstream approach. In this article, the structure and filtration performances of nonwoven filter fibers before and after impregnation with carbon black were tested and analyzed. The results showed that a carbon black coating layer was wrapped on the surfaces of the changed nonwoven fabric filter fibers. The porosity of fibers decreased from 97.81% to 95.35%. The filtration efficiency of PM1.0, PM2.5, and PM10 increased by 16.8%, 28.0%, and 11.7%, respectively, at the best filtration velocity of 0.8 m/s. The filtration efficiency of PM2.5 had the most significant improvement. But the resistance increased by 1.18 times at the same time. The matching between filtration efficiency and resistance should be considered in using. This study provides reference value for the synthesis and application of new filter materials. [ABSTRACT FROM AUTHOR]

Photoinduced network formation is an attractive strategy for designing water-insoluble gelatin fibres as medical device building blocks and for enabling late-stage property customisation. However, mechanically competent, long-lasting filaments are still hard to realise with current photoactive, e.g. methacrylated, gelatin systems due to inherent spinning instability and restricted coagulation capability. To explore this challenge, we present a multiscale approach combining the synthesis of 4-vinylbenzyl chloride (4VBC)-functionalised gelatin (Gel-4VBC) with a voltage-free spinning and UV-curing process so that biopolymer networks in the form of either individual fibres or nonwovens could be successfully manufactured. In comparison with state-of-the-art methacrylated gelatin, the mechanical properties of UV-cured Gel-4VBC fibres were readily modulated by adjustment of coagulation conditions, so that an ultimate tensile strength and strain at break of 25 ± 4–74 ± 3 MPa and 1.7 ± 0.3–8.6 ± 0.5% were measured, respectively. The sequential functionalisation/spinning route proved to be highly scalable, so that one-step spun-laid formation of fibroblast-friendly nonwoven fabrics was successfully demonstrated with wet-spun Gel-4VBC fibres. The presented approach could be exploited to generate a library of gelatin building blocks tuneable from the molecular to the macroscopic level to deliver computer-controlled extrusion of fibres and nonwovens according to defined clinical applications. [ABSTRACT FROM AUTHOR]

An analysis is made of application of Kozeny approach for estimating air permeability of nonwoven needle-punched fabrics based on fibres with 0.33 and 1.7 tex linear densities and a blend of these fibres as well as of treated materials based on polyester and bicomponent fibres. The inverse problem, which boils down to calculation of the Kozeny constant using experimentally derived permeability coefficient of fabrics and materials is solved. The Kozeny constant depends on the composition of the fabrics and materials and diminishes with transition from fabrics made with fibres of different linear densities to treated materials. [ABSTRACT FROM AUTHOR]

Abstract This study investigates the mechanical properties and damage behavior of flexible laminated composites. Needle punching is performed to combine woven Kevlar fabric and two nonwoven low-melting point polyester (LMPET) fabrics into a fabric interlayer. A sheet-extrusion machine is used to bond two thermoplastic polyurethane (TPU) sheets on each side of a fabric interlayer. The tensile strength, peel load, and static puncture resistance of the flexible laminated composites are evaluated, and the influences of needle-punching rates and depths are examined. Test results show that a high needle-punching rate or depth positively affects tensile strength by promoting fiber entanglement. The tensile strength of the 300-15 group reaches 24.70 MPa. Moreover, when the needle-punching depth does not exceed 11 mm, melted LMPET fibers help bond two-phase materials and thus increase the peel loads of the final composites. The 200-11 group has an optimal puncture resistance of 5.86 N. The combination of TPU sheets and woven Kevlar fabrics yields flexible laminated composites with good static puncture resistance. The results of this study can be applied to improve the performance of flexible laminated composites. [ABSTRACT FROM AUTHOR]

Purpose. Determination of thermophysical properties of non-woven materials on the basis of elastic fibrous wastes intended for further use in the composition of biometric packages of belongings of military personnel. Method. Four types of nonwovens made on the basis of the elastic fibrous wastes of the textile industry were investigated. To create a fibrous cloth used a combing machine brand CHBV. The obtained cloths were fastened by the needle punching operation on the VP-1 machine. The thermal conductivity was determined by the dynamic calorimetry method on an IT-λ-400 heat conductivity meter. In order to ensure the necessary reliability of the obtained results, the data were processed using the method of mathematical statistics in Microsoft Excel. Results. Addition to the initial composition of PU/PA-6,6 PET fibers is shown to impair the thermal properties of the material. At the same time, the use of up to 50% by weight of natural fibers of flax and hemp allows to obtain a nonwoven fabric with a sufficiently low coefficient of thermal conductivity (0.15- 0.16 W/(m·K)) with a smaller surface than the original sample. density. At the same time, their specific mass isobaric heat capacity is almost independent of the surface density. Scientific novelty. The regularities of the influence of the composition and surface density of nonwoven materials based on elastic fibrous wastes on their thermophysical properties are established. Practical significance. A composition was proposed and nonwoven materials based on elastic fibrous waste with improved thermophysical properties were obtained that met the requirements of the biometric packages of clothing belonging to servicemen. [ABSTRACT FROM AUTHOR]

Carding is a common web-forming process used for staple fibers in the nonwovens industry. Carded webs can be produced with bicomponent staple fibers designed to split into fine fibers. Splittable bicomponent fibers offer benefits such as increased surface area, improved hand, decreased pore size, improved cover, and enhanced strength. Splittable bicomponent fibers within carded webs can be split and bonded utilizing high-pressure water jets during the hydroentangling process. Staple fibers may be produced in many different lengths. However, the effect of staple fiber length on the nonwoven carding process and structure-property relationships of carded, hydroentangled nonwoven fabrics composed of splittable bicomponent fibers is not well understood. During this research, polyester/polyethylene 16-segmented pie, bicomponent fibers with lengths ranging from 2.54 to 15.24 cm were produced, carded and bonded by hydroentangling. All fiber lengths used during this research were successfully carded, and no significant challenges were observed during carding. Fabric performance was evaluated with air permeability and burst strength testing. Data sets were statistically evaluated with one-way and two-way analysis of variance to determine whether fiber length significantly affected fabric structure and properties. In general, the solid volume fraction and air permeability of the samples were affected by fiber length. However, fiber length did not strongly affect the burst strength of hydroentangled fabrics. [ABSTRACT FROM AUTHOR]

In this work, zinc oxide nanorods are synthesized by polyvinyl alcohol-based sol-gel Pyrolysis method and also applied to prepare the antibacterial ZnO/polypropylene nanocomposite fibers and non-woven fabrics. The fibers are produced by the melt spinning and the nonwoven is produced by thermo banding method. The samples are characterized by SEM and TEM. The antibacterial activity of the fibers is qualitative assessed by the agar diffusion and parallel streak and quantitative test methods for percentage reduction of bacteria colonies. The topographical analysis of the treated fiber and untreated fiber are studied and compared. The results show that the treated fibers and non-woven fabrics have the significant antibacterial and antiallergic properties. In addition, the samples show good mechanical strength and UV protection. [ABSTRACT FROM AUTHOR]

The air drawing model of polymer polypropylene (PP) spunbonding nonwovens has been established. The influences of the density and the specific heat capacity of polymer melt at constant pressure changing with polymer temperature on the fiber diameter have been studied. The air drawing model of polymer in spunbonding is confirmed by the experimental results obtained with our university's equipment. The effects of the processing parameters on fibers web evenness of PP spunbonding nonwoven fabrics in wide slot positive pressure drafting assembly of spunbonding process have also been investigated. The predictions of the filament fiber diameters, crystallinities, and birefringences are coincided well with the experimental data. It is found that a medium polymer melt temperature, monomer suction wind speed, drawing pressure, cross air blow speed, and air control distance have a significant influence on the web evenness and quality, which are beneficial to produce more uniformity fibers web. The experimental results show that the agreement between the results and experimental data is very better, which verifies the reliability of these models. At the same time, the results also reveal the great potential of this research for the computer‐assisted design (CAD) of spunbonding technology. POLYM. ENG. SCI., 58:1268–1277, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]