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It was aimed to determine the specific resource use and reduction potential profiles in various textile sub-sectors (cotton woven fabric dyeing-finishing, wool woven fabric dyeing-finishing, synthetic woven fabric dyeing-finishing, cotton knitted fabric, synthetic knit fabric dyeing-finishing, non-woven fabric, dyeing-finishing of knitted fabric). The main focus was to elucidate opportunities for sustainability in terms of decreasing resource utilization in the textile sector. On-site surveys and detailed data collection studies were carried out at 150 textile facilities. Average specific values for water, auxiliary chemicals, dyestuff, electricity, and steam consumptions, and related reduction potentials were calculated and compared within facilities and sub-sectors. The minimum specific resource consumption values reported in the Best Available Techniques Reference Document (BREF) for the textile industry and data of similar facilities from the literature were evaluated and used. A detailed environmental performance profile of the Turkish textile sector in terms of resource usage and reduction potential was generated. The highest specific water consumption was found in the wool-woven fabric sub-sector (345 ± 262 L/kg product). Although the specific auxiliary chemical consumption shows similarities within sub-sectors, the highest specific auxiliary chemical consumption (397 ± 237 g/kg product) was found in the synthetic woven fabric sub-sector. The sub-sector with the highest specific dyestuff consumption (30 ± 13 g/kg product) was the cotton knitted fabric sub-sector. The wool woven fabric industry had the highest specific electricity (7 ± 5.3 kWh/kg product) and steam (20 ± 11 kg steam/kg product) consumption. In addition, for all the studied sub-sectors country-wide, the lowest and highest reduction potentials in resource uses were 18 ± 15% and 73 ± 13%, respectively, suggesting a need for major full-scale implementations of cleaner production for enhancing sustainability in the textile industry. [ABSTRACT FROM AUTHOR]

In this world, unnoticed sound that disturbs frequently is called as noise. It is one of the main reasons for reducing the environment quality of human being. This effect can be minimized by using acoustic absorbent material in different areas where the sound absorption is required. In textile, acoustic property of non-woven is better than the woven fabric. The non-woven fabrics were developed using the needle punching technique using kapok, jute, flax, viscose, polyester, polypropylene, and recycled polyethylene terephthalate (R-Pet) fibers. Sound absorbency parameter was tested by sound absorption tester specially designed for this purpose. The effects of fiber type, number of layers in the fabric, thickness of the sample, areal density, air permeability, and pore size on sound absorption capacity were investigated in this research work. Experimental results show that 100% kapok non-woven fabric with its high compact structure, higher thickness, lesser air permeability, and less average flow diameter exhibit good sound absorption property than other samples, and it is best-suitable for interior in automotive applications for noise control. [ABSTRACT FROM AUTHOR]

Water pollution is a big issue of our world. This research aims to study the possibility of using carboxylate functionalized synthetic nonwoven fabrics for removing heavy metals from contaminated water. Poly(acrylic acid) (PAA) and poly(itaconic acid) (PIA) were grafted from the surfaces of individual Nylon 6,6 fibers of nonwoven fabrics by radiation inducedpolymerization with Gamma-rays under various conditions. FTIR spectra show evidence of the carboxylate groups of PAA and PIA after polymer grafting. A comparison of fiber sizes and surface morphology of nonwoven Nylon fabrics before and after PAA and PIA grafting was examined using optical microscopy (OM) and scanning electron microscopy (SEM). The shrinkage, curl and non-uniformity of fibers observed by OM and SEM after polymer grafting might cause the changes in the water permeabilities of the modified Nylon fabrics. After hydrolyzation of modified Nylon fabrics with sodium hydroxide, static cadmium (Cd2+) ion exchange capacities were measured for all fabric samples. The Langmuir model was used to calculate parameters, including maximum static Cd2+ ion exchange capacities and the association coefficients to explain behaviors of unmodified and modified nonwoven Nylon fabrics. Using unmodified and PAA- and PIA- modified Nylon fabrics as ion-exchange membranes, these membranes provide higher water flowability than conventional membranes. Furthermore, the static Cd2+ ion exchange capacities of these ion-exchange membranes are comparable to commercial ion-exchange materials. It was also found that duration time of radiation inducing and heating steps along with various types of polymer grafting affected the ion exchange capacities and membrane performance. [ABSTRACT FROM AUTHOR]

Air permeability of processed nonwoven needlepunch cloth fabricated from fibers of various linear densities and a bicomponent fiber was studied. The processing regime and an increase of bulk density were shown to affect the cloth air permeability. A model for predicting air permeability was developed based on a complex structure parameter. [ABSTRACT FROM AUTHOR]

A suite of programs is developed to analyze photomicrographs of the structure of nonwoven materials. Such programs are needed for deciphering the structural distinctions in multidimensional characteristics of the studied objects that contain information about their states. This allows their use for classification of objects describable by characteristics of a different physical nature without their pre-standardization. The explicit form of the proposed measures is given and the effectiveness of their use in algorithms for automatic classification is shown for clustering of the images of polypropylene spunbond nonwoven material. [ABSTRACT FROM AUTHOR]

A comparative study was conducted to identify the effects of processing on physical and combustion properties of needlepunched (NP) and hydroentangled (H-E) nonwoven fabrics produced from fibers of white fiber cotton and a naturally colored brown fiber cotton. A significantly higher degree of flame retardancy (FR) in was observed in fabrics produced from brown cotton fibers compared with white fibers. Calorimetry revealed lower heat release capacity, lower peak heat release rate, and total heat release from brown fibers compared with white fibers. The ash content was also higher in brown fiber samples suggesting higher levels of inorganic elements in the brown fibers. Elemental analyses revealed brown cotton fibers had higher levels of known FR elements including phosphorous and magnesium. The H-E process reduced FR in brown fabrics, which also correlated with a reduction in phosphorous. However, brown H-E fabrics still maintained higher FR than white H-E fabrics. Water content analysis indicated higher water levels in brown fibers, particularly brown greige fibers, which correlated with increased FR. Processing parameters such as energy of H-E did not affect combustion of the two fabric types. Scouring of the brown fiber fabrics reduced, but did not remove coloration, while scouring and bleaching removed the brown color completely. Scouring alone, or scouring and bleaching, completely removed the higher FR properties of the brown fiber fabrics. The results indicate that the mechanism of FR in brown cotton fibers is dependent on multiple compositional factors that may include element content, water content, and compounds related to coloration. [ABSTRACT FROM AUTHOR]

The effect of different fiber blend ratios and bulk densities at similar thicknesses on air permeability and sound absorption coefficient was investigated. The raw materials used were cotton, polyester, and bi-component fibers to make acoustic nonwovens through the air-laid and thermal bonding processes. A uniform thermal-conductivity box was designed in order to make thermally bonded nonwovens with fixed thicknesses. The experimental results depict that the air flow resistance of three-layer nonwoven was 0.565 kPa⋅s/m, which was about four times greater than one-layer of 0.12 kPa⋅s/m. Sound absorption coefficient of 20% polyester-60% cotton-20% bicomponent nonwoven with lower bulk density was greater than the 60% polyester-20% cotton-20% bicomponent nonwoven. The sound absorption coefficient varied based on which fabric side faced the testing apparatus. [ABSTRACT FROM AUTHOR]

Antimicrobial non-woven polyethylene terephthalate (PET) fabric containing nano-silver of different concentrations has been prepared in a novel three step process. Nano-silver has been incorporated in between two layers of organosilicon thin film deposited by an atmospheric pressure plasma system. The top layer of 10 nm thickness was used as a barrier to prevent release of nanoparticles from the surface. The antimicrobial activity of the nano-silver fabrics was tested using Staphylococcus aureus and Escherichia coli by a dilution method. The effect of silver concentration on the lag phase, the specific cell growth rate, and the cell concentration has been studied and discussed based on bacterial growth curves. [ABSTRACT FROM AUTHOR]

Sound pollution has become an important issue that has been addressed by scientists of various disciplines. Control of sound in areas of transport and building industries is of paramount importance. Textiles are widely used as sound insulators. Among the broad spectrum of textiles, nonwoven fabrics due to their technical merits and wide acceptance are extensively used as sound controlling media. In this work, various blends of polypropylene and naturally grown hollow Estabragh fibers were used to prepare sound absorptive nonwoven layers. The fiber blends were fed to a laboratory scale carding machine. Carded webs were lightly needled on a laboratory scale needling machine. Acoustic properties of needled samples were evaluated using the Impedance tube method. The Taguchi method was used to analyze the effective parameters influencing fabric acoustic properties. Results show that the proportion of Estabragh fibers in the blends strongly affects the noise absorption coefficient (NAC). Frequency is the second effective factor and is followed by nonwoven layer mass (areal density) and punch density, respectively. It was concluded that layers comprised of 100% Estabragh fibers achieved the highest value of NAC. The results also pointed to existence of a direct correlation between noise absorption coefficient and the amount of punch density exerted during needling process. It was found that the increase in the amount punch density resulted in higher values of NAC. [ABSTRACT FROM AUTHOR]

Ultrasonic seam strength and elongation at break properties of thermal bonded nonwoven fabrics are discussed in this study; and the effects of fiber type, fabric area density, and roller type on ultrasonic tensile properties of nonwoven fabrics are reported. Polypropylene (PP), Polyester (PES), and Polyamide - Polyester (70% PA - 30%PES) blend of thermal bonded nonwoven fabrics were used, and the seam strength and elongation at break were measured and the obtained data were evaluated. At the end of the experimental studies, the data from the ultrasonic tensile properties of thermal bonded nonwoven fabrics which were made of different fibers and same production method were evaluated in order to determine the tensile properties which lead to the best result. The experimental results show that the PP thermal bonded nonwoven fabric tended to provide the best seam strength and elongation at break values. [ABSTRACT FROM AUTHOR]

The hydroentanglement process is highly energy intensive compared to other methods of manufacturing nonwoven fabrics. This paper presents an exploratory study on optimizing the usage of hydroentanglement energy so as to lower the processing cost. The experiments were based on a Box–Behnken experimental design (BBD) and multivariate linear regression analysis to model the tensile strength as response to variables. Three variables were selected, namely fabric area weight (150–400 g/m2), machine speed (5–15 m/min) and waterjet pressure (40–200 bars). These parameters were employed in two sets of experiments to achieve maximum tensile strength of viscose nonwoven fabrics. The first experiment was conducted using higher waterjet pressures of 100, 150 and 200 bars, which were proved to have exceeded the optimum levels. The second experiment was conducted at relatively lower waterjet pressures of 40, 60 and 80 bars. The results on tensile strength were analyzed using the SYSTAT 10 software package and response surface plots were prepared. The linear, quadratic and interactive effects of the main variables were shown to be significant. Interactions amongst the variables were found to have either a synergistic (positive) or offsetting (negative) relationship with the fabric tensile strength. The interactions involving machine speed were predominantly offsetting. The 400 g/m2 area weight fabric produced at 80 bars of waterjet pressure achieved a fabric tensile strength of 222 cN, which compared favorably with that of 232 cN obtained at 200 bars of waterjet pressure. In this exploratory study using BBD, linear, quadratic and interactive effects were observed to be significant and the usage of hydroentanglement energy was successfully optimized. This indicates the possibility of achieving high fabric strength but at lower waterjet pressures; in other words, by employing low hydroentanglement energy and thereby minimizing the processing cost. [ABSTRACT FROM PUBLISHER]

It is widely recognized that nonwoven basis weight uniformity affects various properties of nonwovens, including appearance, physical properties, or mechanical properties. However, it is one of the nonwoven characteristics that is most difficult to characterize. This paper reports on the methodology based on the well-known quadrant method that objectively quantifies uniformity of nonwoven fabrics. [ABSTRACT FROM AUTHOR]

Purpose. Determination of thermal properties of multicomponent nonwoven fabrics, obtained on the basis of cotton regenerated fibers. Methodology. Differential thermal and thermogravimetric methods were used, with the help of which the process of thermooxidative destruction the nonwoven fabric was interestgated. Findings. It was two-stage destruction of the sample during the investigations thermogravimetric of nonwoven, which indicates that a part of the nonwoven fabric enters except of regenerated cotton fibers, and at least two components. Originality. Thermogravimetry analysis of multicomponent nonwoven fabric showed, that under the influence of temperatures, destruction processes have to place in the components and the properties of the starting materials are not changed. Practical value. The defined absence of the destruction processes at the temperature 200 °C gives the possibility to use the investigated nonwovens as the components in multilayered thermobonding textile fabrics. [ABSTRACT FROM AUTHOR]

Spunlaced nonwoven fabrics have been widely used recently, but fundamental research on the spunlaced nonwoven process is relatively weak. It is inexplicit until now how fibers are entangled with each other during the hydroentangling process. In this paper, a pull-out experiment designed to study the entanglement properties of spunlaced nonwoven fabrics using common and hydrophilic PET fibers as objects is described. It was found that the broken fiber content can be used to represent the entanglement intensity of the spunlaced nonwoven fabrics. In addition, a formula was set up to calculate the tensile strength of the spunlaced nonwoven fabric based on its pull-out behavior. [ABSTRACT FROM AUTHOR]

Due to numerous developments in most industries and the increase in the usage of massive and powerful machines in every field, noise has become an unavoidable part of mechanized life and has brought about serious health hazards. The main aim of this work was to investigate the usability of polyurethane and polyacrylonitrile nanofibers for improving sound insulation properties over a wide band of frequencies and reducing weight and thickness of conventional polyester and wool nonwovens. The effect of the number of nanofiber layers and associated surface densities on acoustic properties was investigated. Sound transmission loss and sound absorption analysis using the impedance tube method were carried out as the main factors affecting acoustic behavior of samples. The results show that incorporation of nanofiber layers in nonwoven materials can improve both sound absorption and sound transmission loss simultaneously, especially in mid and lower frequencies, which are difficult to detect by conventional materials. [ABSTRACT FROM AUTHOR]

An analysis of the basic properties of geotextiles obtained by two-sided needle punching and by two-layered needle punching on the fabric underlay is presented in this paper. The influence of geotextile production technology on their functional properties was evaluated, the parameters of geotextiles manufactured from staple fibres by mechanical needle punching were compared for both techniques, and the influence of the mass per unit area on the mechanical and hydraulic properties is shown. It was found that geotextiles obtained by two-sided needle punching had very good hydraulic properties thanks to their spatial structure, whereas geotextiles obtained by two-layered needle punching on the fabric underlay, apart from good hydraulic properties, had very good tensile strength and small elongation at a maximum load, which is particularly useful for reinforcement. [ABSTRACT FROM AUTHOR]

As a method for producing nonwovens with ultrafine fibers, melt blown technology has been developing rapidly. The development status quo of this technology was introduced in this paper, in terms of production technique,raw material used and products' application. Furthermore, the authors gave some points on the developing trends of this technology. [ABSTRACT FROM AUTHOR]

With nonwovens production line going for large-scale, high-speed and high efficiency, the nonwovens roll goods tend to be off-line with full width and no cutting and slitting, thus off-line slitter has been a significant part for the production line. Main function and application of off-line slitter were introduced in this paper, as well as technology development status quo. Besides, the structure and control system of this kind of device were stated in detail. [ABSTRACT FROM AUTHOR]

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A new instrument and a test method are presented in this paper that can evaluate the stiffness of plain weft-knitted fabrics. The WIRA Instrumentation Tester can measure torsion data for various flexible fibre assemblies whilst they are being twisted. The torsional properties of two types of fabrics, namely nonwoven and knitted fabrics, were analyzed. Then, comparisons between bending rigidity and torsional rigidity have been conducted using FAST-2, Shirley, Heart Loop and the new WIRA method for the assessment of fabric stiffness. The results show high correlation between bending rigidity and torsional rigidity in assessment of nonwoven fabric stiffness; they also reveal that the WIRA tester and torsional rigidity are more suitable for characterizing the stiffness of plain weft-knitted fabrics than the other test methods [ABSTRACT FROM AUTHOR]

Nonwovens are manufactured by different methods such as dry laying, wet laying, spunbonding and melt blowing. This paper discusses the processing of chopped fiberglass strands to form nonwoven webs using the wet laying process. Chopped fiberglass strands are used to manufacture fiberglass mats and also mixed with resins to form composites. In this project these strands were used to manufacture nonwoven webs by the wet laid method. Modification of the paper hand sheet making method was necessary at the stage of web formation and bonding in order to overcome problems caused by the stiffness and inert nature of glass fibres, as compared to pulp. The ibre orientation of the fiberglass webs was analysed using the Fast Fourier Transform, in which it was found that in most of the fiberglass webs, the ibres were oriented randomly. [ABSTRACT FROM AUTHOR]

Nanofiber yarns with controlled twist levels were prepared by twisting a narrow fibrous strip cut directly from electrospun nanofiber mats. The effects of fiber morphology, diameter and orientation, as well as the yarn twist level on the yarn tensile properties were examined. For the yarns made from randomly oriented fine uniform nanofibers (e.g., diameter 359 nm) and beaded nanofibers, the tensile strength increased with increasing the yarn twist level. Higher fiber diameter (e.g., 634 nm) led to the tensile strength having an initial increase and then decrease trend. The modulus increased with the twist level for all the yarns studied. However, the elongation at break increased initially with the twist level and subsequently decreased. The orientation of aligned fibers within the fiber strip greatly influenced the yarn tensile properties. When the fibers were oriented along the fiber length direction, both tensile strength and modulus were the largest. [ABSTRACT FROM PUBLISHER]

Two medeling techniques are introduced to predict the sheet resistance of electrically conductive continuous filament nonwoven fabric; a two-dimensional (2-D) discrete filament stochastic resistor network simulation, and a simple analysis using a laminate analogy. The effects of anisotropy and sample size are considered. Results are compared with experiments on a silver coated point bonded nylon nonwoven fabric. For this particular sample, experimental sheet resistance results are significantly under-predicted by the 2-D analytical and simulation approached where perfect inter-filament bonding is assumed. The utility of the 2-D perfect bonding predictions as an ultimate lower bound on the sheet resistance that may be achieved by extremely well-bonded continuous filament networks is discussed. Simulations of 2-D filament webs with poor inter-filament bonding and moderate anisotropy are shown to agree will with the present experiments. Taken together, the present results suggest that modeling of the in-plane conduction behavior of a general continuous filament nonwoven fabric requires a 3-D structural approach to capture the effect of an appropriate number density of inter-filaments bonds. [ABSTRACT FROM AUTHOR]

Nonwovens are very important sound absorption materials used by the automotive and building industries. One of the most important fabric parameters that affect the sound insulation and absorption properties is the surface area. Higher surface area is often achieved by using low-diameter fibers in the insulation material. This research was done to prove that neither the thickness nor the weight of the material is as important as the total surface area of the fabric. Glass beads with 0.1mm, 0.5mm and 2.5mm sizes, which do not contribute considerably to the total surface area of the fabric, were imbedded into cross-lapped and needlepunched nonwoven structures. These beads were added in weight percentages of 25%, 50%, 75%, 100% and 200%. Sound insulation of glass bead imbedded nonwoven fabrics was tested using Clemson Boston Sound Insulation Tester. It was found that the micro- glass beads did not have a large impact on the sound insulation, as they do not contribute to the surface area of the nonwoven fabric. The samples with 0.1mm beads performed slightly better than samples with larger beads but not enough to make a significant difference. Since surface area is the major parameter that affects sound insulation, simply increasing the weight does not affect the sound insulation property of the material. [ABSTRACT FROM AUTHOR]

This paper presents methods for the preparation of systems composed of polylactide (PLA) nonwoven and selected bioacceptable polymers such as poly(acrylic acid) (PAA), Carbopol, poly(N,N-dimethylaminoethyl methacrylate), (PDAMA), alginic acid (AlgA), chitosan (CHN) and gelatin. The modification was performed by the method of padding or entrapping. The possibility of further modification by the layer-by-layer (LbL) deposition method was also examined. The moisture absorption and water retention by the systems obtained were determined. Changes in the surface electric charge under the influence of the layers successively deposited and the biological activity of selected systems were examined. [ABSTRACT FROM AUTHOR]

PLA fiber and its products is a research hotspot for global man-made fiber industry, among which, in the field of PLA spunbond nonwovens, some enterprises and institutes in Japan have made great improvements, and Chinese researchers and manufacturers have been speeding up their paces. This article introduced the production of PLA spunbond nonwovens in terms of spinning process, equipment selection, factors influencing the performance of products, et al., anticipating to provide some references for those who are interested in this field. [ABSTRACT FROM AUTHOR]

SMS (spun-melt-spun) is one of the typical high performance spunlaid technologies, and fiber web bonding with calender is the main process for this technology. Based on the introduction of the performance, product application of SMS technology, as well as some key properties of calenders in the market, this article stated that it is necessary for nonwovens production line manufacturer to consider the performance of spunlaid system, products' target market and economical efficiency when choosing a calender. [ABSTRACT FROM AUTHOR]

Two types of nonwoven fabric, consisting of siloxane-doped vaterite (SiV) and poly(lactic acid) (PLA), for guided bone regeneration (GBR) were prepared by an electrospinning. One of the fabrics, S1V-PLA(M), was derived from PLA mixed with the solution of SiV dispersed in chloroform. Another one, SiV-PLA(K), was derived from a composite prepared by kneading SiV and PLA while heating at 200°C. The SiV-PLA(K) fabric shows higher degradabiity in dilute NaOH aq. than the SiV-PLA(M) fabric. To improve the cellular compatibility of the fabric, the fibers were coated with hydroxyapatite (HA) by soaking in simulated body fluid. The HA-coated SiV-PLA(K) fabric showed the release of silicate ions; the amount was reduced by 1/5 to 1/8 compared with that of the HA-coated SiV-PLA(M) fabric, and the excessive release was controlled. The preparation route of kneading at 200°C led to formation of a fabric with degradation behavior and ion releasability effective for bone regeneration. [ABSTRACT FROM AUTHOR]

The change in the properties, such as tensile characteristics, compressional behaviour and air permeability, of a wide range of polypropylene heat-sealed spunbonded nonwoven fabrics has been studied after cyclic bursting pressure. It is observed that the cyclic bursting pressure results in change in tensile, compressional and transmission characteristics of fabrics to a great extent. The air permeability is found to be increased after the application of cyclic pressure, whereas the compressibility and recovery tendency increase marginally after the application of cyclic pressure. The cyclic bursting pressure also have significant impact on the tensile strength of spunbonded nonwoven fabrics. The tensile strength reduces after the application of cyclic pressure. The increase in the pressure level during cyclic loading significantly decreases the tensile strength. [ABSTRACT FROM AUTHOR]

The compressional and recovery behaviour of highloft nonwovens has been studied with a view to know how the fibre materials used and manufacturing technologies employed drive and dictate this behaviour. The results show significant effects of physical and mechanical properties of fibres on the compressional and recovery behaviour of highlofls. It is also observed that highlofts produced by different bonding technologies show significantly different compressional and recovery behaviour. The experimental results are found in satisfactory agreement with the theoretical results. [ABSTRACT FROM AUTHOR]

This paper presents a study on the sensing properties of a conductive polymer composite (CPC) that is processed by an electrospinning technique. The CPC is obtained by mixing multi-walled carbon nanotubes (MWNT) with a poly (ethylene oxide) (PEO) matrix. Sensors made of this composite are characterised by measuring their electrical properties as a function of external stimuli. In particular, their responses to vapours of toluene, methanol and dioxan are investigated. As studied, the PEO/MWNT material shows high and stable sensitivity over three testing cycles for the selected vapours. An increase in electrical resistance is observed under the influence of chemical substances. This paper supports the concept that penetration of molecules of selected chemical substances leads to the partial disorder of contact between neighboured nanotubes located in the polymer matrix. The electro-spun non-woven fabric with a low amount of MWNT (3 wt.%) in the PEO matrix seems to be a good textile product for application as sensing membranes in personal protective clothing. [ABSTRACT FROM AUTHOR]

This study utilized a 3D crimped hollow fiber web and high tenacity nylon-6 fiber web blended with low-melt polyester staple fibers to form a compound nonwoven fabric with a sandwich structure processed by needle punching and thermal pressing. The compound nonwoven fabric was layered with Kevlar fabric to form bullet-resistant complex fabrics. Impact properties and buffer effect were analyzed via the drop weight impact test and the bullet-shooting test. The compound nonwoven fabrics made of high-tenacity nylon-6 fiber and 3D crimped hollow fiber increased the buffer effect of ballistic resistance and decreased non-penetration damage and the layer of Kevlar fabrics. This study was expected to increase the safety of the ballistic resistant cloth and decrease its cost. [ABSTRACT FROM AUTHOR]

Fibrous polymers with extremely low electrical conductivity such as polypropylene (PP), polycarbonate, polyurethane, and polyethylene are commonly employed as air-filter materials. The charge accumulated on such materials due to tribocharging effects inherent to the manufacturing process might be harmful either to the operator or to the electronic equipment of the production line. Whenever charge buildup cannot be avoided, it is important to have an effective method available in order to rapidly discharge the materials. The present work aims to evaluate the efficiency of active neutralization of charged nonwoven fabrics. The experiments have been carried out on 0.4-mm-thick PP and polyester fibrous media, with the average diameter of the two types of fibers being 28 and 19 µm, respectively. The nonwoven fabrics were charged by exposing them to a negative corona discharge generated by a wire-grid-plate electrode system. The samples, laid on the surface of the grounded electrode or suspended at a small distance (4.6 mm) above it, were then subjected to the action of the bipolar ions generated by a commercial neutralizer (model 6430, Ion Systems Inc., Berkeley, CA). The monitored variable was the surface potential detected by the probe of an electrostatic voltmeter. The controlled variables were the potential of the grid electrode, the neutralization time, and the distance between the neutralizer and the media. The results of the experiments enabled a crude evaluation of each factor effect. Research should continue, using the experimental design methodology, in order to establish the optimum conditions for charge neutralization. [ABSTRACT FROM AUTHOR]

Pore size distribution is a prerequisite to investigate any transport phenomena, especially in a porous structure such as nonwovens. The pores inside the nonwovens are highly complex in terms of the sizes, shapes and the capillary geometries. The majority of existing theories/models of pore size distribution of nonwovens do not account for the fibre orientation distribution characteristics. In this research work, the model for predicting the pore size distribution of nonwoven structures has been developed by combining the stochastic and stereological or geometrical probability approaches. These techniques have incorporated the effects of fibre orientation characteristics in nonwoven structures. The analytical model formulated is compared with the existing theories to predict the pore size distribution of nonwoven structures. A comparison is also made between the experimental and theoretical pore size distributions of spun-bonded and needle-punched nonwovens. The effect of various fibre and fabric parameters including fibre volume fraction, fibre orientation distribution characteristics and number of layers on pore size distribution of nonwoven structures has been investigated. [ABSTRACT FROM AUTHOR]

This study used nonwoven fabrics as the matrix of a composite dressing and coating with different gelatin-anthocyanin ratios (10/0 wt%, 10/5 wt%, and 10/10 wt%). The anthocyanin reduced gelatin degradation rate, epithelialization rates increased, and deposition of collagen in the wound dermis was well organized by the composite wound dressing. This composite containing gelatin and anthocyanin can be employed as a wound dressing. [ABSTRACT FROM AUTHOR]

Abstract: An activated carbon fiber nonwoven (ACF) was manufactured from a cotton nonwoven fabric. For the ACF acoustic application, a nonwoven composite of ACF with cotton nonwoven as a base layer was developed. Also produced were the composites of the cotton nonwoven base layer with a layer of glassfiber nonwoven, and the cotton nonwoven base layer with a layer of cotton fiber nonwoven. Their noise absorption coefficients and sound transmission loss were measured using the Brüel and Kjær impedance tube instrument. Statistical significance of the differences between the composites was tested using the method of Duncan’s grouping. The study concluded that the ACF composite exhibited a greater ability to absorb normal incidence sound waves than the composites with either glassfiber or cotton fiber. The analysis of sound transmission loss revealed that the three composites still obeyed the mass law of transmission loss. The composite with the surface layer of cotton fiber nonwoven possessed a higher fabric density and therefore showed a better sound insulation than the composites with glassfiber and ACF. [Copyright &y& Elsevier]

This paper reports a study on the thermoregulation properties of PCM nonwovens. Microencapsulated n-alkanes (n-octadecane and n-eicosane) dispersed in a polymer binder (acrylic-butadiene copolymer) were applied to needled and hydroentangled nonwovens by the pad-mangle or screen printing method. The surface morphology and cross section of PCM nonwovens were observed by means of scanning electron microscopy (SEM). The thermal storage/release properties of the nonwoven samples treated with microPCMs were analysed by DSC, and the thermal resistance of the nonwovens under steady state conditions was determined by means of a sweating guarded hotplate instrument. The transient thermal performance of the nonwoven samples containing microPCMs was examined using novel apparatus with a dynamic heat source. The temperature regulating factor (TRF), defined by Hittle, was determined for selected cycle times of heat flux changes (t), the results of which are shown in diagrams presenting the relation TRF = f(t). The results obtained show that the main factor determining the TRF value is the amount of latent heat in a unit area of nonwoven fabric. Thermoregulating properties of the printed nonwoven sample with microPCMs are identified as being dependent on the position of the microPCMs layer. This work shows the possibility of achieving a significant thermoregulation effect even with moderate amounts of microPCMs incorporated at a proper location in the nonwoven system. [ABSTRACT FROM AUTHOR]

An air-drawing model of the polylactic acid (PLA) spunbonding process is presented and solved by introducing numerical computation results of the air jet flow field of an aerodynamic device. At the same time, the model is also verified by experimental results obtained with our university's equipment. The influence of the density and specific heat capacity of polymer melt at a constant pressure changing with the polymer temperature on the fibre diameter was studied. The fibre diameters predicted is in good agreement with experimental data. The effects of processing parameters on the fibre diameter are further analysed. We find that a lower polymer throughput rate, a higher initial temperature of the melt,a higher initial temperature, velocity, and suction speed of the air can all produce finer fibres, but during the incruse in the venturi gap, the fibre diameters first decrease and next increase again. The results encourage us to further investigate how fine a fibre diameter can be obtained in the spunbonding process and what factors influence the fibre diameter formed. Furthermore, the results also show the great perspective of this research in the field of the (CAD), of the spunbonding process and technology. [ABSTRACT FROM AUTHOR]

The apparent contact angles of a droplet deposited on the surfaces of thermal-bonded nonwoven fabrics were presented, and the characteristics required for a superhydrophobic surface were described. For a nonwoven superhydrophobic surface, the Cassie–Baxter model describes the wetting of rough surfaces. Using topological and chemical surface modifications of nylon 6,6 nonwoven fabric, artificial Lotus leaves having water contact angles >150° were prepared. Good agreement between the predictions based on the original Cassie–Baxter model and experiments was obtained. The angle at which a water droplet rolls off the surface has also been used to define a superhydrophobic surface. Superhydrophobic surfaces were prepared by two criteria: a low-surface energy and a properly designed surface roughness. [ABSTRACT FROM AUTHOR]

The work focuses on the development of a new process to flame retard nonwovens, using films based on renewable resources. Films consist in intumescent formulations of polylactic acid (PLA), ammonium polyphosphate (APP) blended with lignin or starch and are coated on hemp or wool nonwovens. The objective of this study was to investigate the fire retardant and mechanical properties of textiles protected by FR PLA films for potential use in building applications. Horizontal and vertical flame spread tests as well as cone calorimetry tests show that flammability properties of nonwovens are significantly improved. Better mechanical properties are also obtained with coated nonwovens. [ABSTRACT FROM AUTHOR]

A computational fluid dynamics (CFD) modelling of the through-air bonding process of nonwoven fabric production is reported in this article. In the through-air process, hot air is passed through the fibrous web to heat and melt polymer fibers. Molten polymer subsequently flows to the point of contact between any two fibers to produce a bond. Two different modelling strategies are adapted to produce a comprehensive understanding of the through-air bonding process. In macroscale modelling, a CFD model is developed treating the whole web as a porous media in order to investigate the effect of process parameters. Results reveal that the time required to heat and melt the fibers decreases with the increasing porosity of the web and the velocity of hot air. The CFD modelling technique is then used to analyze the bonding process at a more fundamental level by considering the bonding of individual fibers at microscale. The effects of the fiber diameter, bonding temperature and contact angle between two fibers on the bonding time are investigated. Results show that the time required to bond fibers is weakly related to bonding temperature and fiber diameter. Fiber orientation angle, on the other hand, has significant effect on the progression of bond formation. [ABSTRACT FROM AUTHOR]

Thermal bonded non-wovens are subjected to compression during their end-use performance in various technical and industrial applications. An attempt has been made to apply the previous theories of compression to formulate a simple two-dimensional (2D) micromechanical model of thermally bonded non-woven structures. The 2D model has incorporated the basic fibre parameters and properties including fibre volume fraction, proportion of free fibre length between two bonds, fibre modulus and an integral defining the orientation characteristics of fibres. A comparison is made between the experimental and theoretical pressure-thickness curves. The effect of fibre orientation characteristics and volume fraction on the compressional behaviour of thermally bonded non-wovens has also been investigated. [ABSTRACT FROM AUTHOR]

This study investigates the screen printing of transmission lines into a variety of nonwoven substrates using different conductive inks for durable and wearable electronic textile applications. The viscosity of the ink dictated the performance of the printed media during washing trials. The printed inks begin to degrade and display lower conductivity after 25 wash cycles. A method to control the durability of the printed circuits, which includes coating of the printed lines with a meltblown layer, has been developed. [ABSTRACT FROM AUTHOR]