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Nonwovens have wide application areas due to their advantageous properties like low cost, high production efficiency, and tuneable properties. They are mostly used for disposable products. Combining bicomponent fiber spinning with hydroentanglement method is one of the innovative methods to obtain nonwovens for durable applications. On the other hand, ultrasonic welding is an alternative assembling method for disposable products made of low weight nonwovens. In this study, the ultrasonic weldability of relatively heavier weight and thicker nonwoven fabrics made of polyester: polyamide bicomponent microfilaments were examined in order to combine the advantages of nonwovens and ultrasonic welding. Relatively higher thickness and weight, and also fiber composition of the nonwoven fabrics were compelling effects of the study that drove the motivation. Overall 60 samples were produced using five nonwoven fabrics with varying unit masses and 12 selected ultrasonic welding types. Seam strength and strain assessments were supported with stereomicroscope and visual inspections in evaluating the welds. Results showed that despite having thick seam lines up to 1.6 mm, successful welded seams could be obtained. Depending on the welding parameters, seam lines of some samples exhibited waviness, color changes, and deformations but these situations did not drastically affect the seam strength of samples. [ABSTRACT FROM AUTHOR]

With rapid advances in electronic and communication technology, electromagnetic interference and other problems are becoming increasingly prominent. Thus, electromagnetic interference shielding materials have recently garnered extensive attention. In this study, a multi‐walled carbon nanotube/polyurethane/non‐woven electromagnetic shielding material (CPNW) is developed using impregnation and nonsolvent‐induced‐phase separation techniques. Utilizing a three‐dimensional nonwoven network as the substrate, the "nonwoven fabric‐polyurethane‐carbon nanotube" composite is impregnated and cured via the non‐solvent‐induced‐phase separation method, resulting in a distinctive porous dual‐network structure that ensures robust interfacial bonding between carbon nanotubes, nonwoven fabric, and polyurethane. At a carbon nanotube content of 10% (based on the mass of nonwoven fabric), CPNW exhibited an electromagnetic interference shielding effectiveness of 28.8 dB, a thermal conductivity of 0.127 W m−1 K−1, and a burning time of 1 min and 15 s, demonstrating outstanding electromagnetic shielding, flame retardant, and infrared stealth capabilities. Overall, this study laid a theoretical groundwork for the development of multifunctional non‐woven electromagnetic shielding materials with widespread application potential in aerospace, military, artificial intelligence, and wearable electronics. [ABSTRACT FROM AUTHOR]

A natural polysaccharide‐based smart photo‐actuator is fabricated via electrospinning of cellulose 4‐phenyl azobenzoate (Azo‐Cel) from its organic solution in a mixture of high‐volatile acetone, a poor solvent of Azo‐Cel, and low‐volatile N,N‐dimethylacetamide (DMAc), a good solvent of Azo‐Cel. At an optimal polymer concentration (17 wt%) and solvent mixing ratio (acetone/DMAc = 3/2 (v/v)), stable electrified polymer jets are formed and continuous nanofibers and their nonwoven fabric can be drawn on a cylinder‐shaped rotating drum electrode under a high electric field (25 kV). Scanning electron microscopic observation of the Azo‐Cel fabric confirms that the fabric consists of uniaxially aligned nanofibers with a mean diameter of 207 nm. The water contact angle of the Azo‐Cel fabric reversibly decreases and increases in response to alternate irradiation with UV and visible light to induce geometric deformation of the azobenzene moiety between the trans and cis isomers, which lead to lower and higher surface free energies, respectively. In addition, self‐standing Azo‐Cel fabric exhibits a UV‐driven photo‐mechanical asymmetric bending deformation toward the light source. [ABSTRACT FROM AUTHOR]

High‐performance multifunctional textiles are highly demanded for human health‐related applications. In this work, a highly conductive nonwoven fabric is fabricated by coating silver nanowires (AgNWs)/poly(3,4‐ethyl enedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) on a poly(m‐phenylene isophthalamide) (PMIA) nonwoven fabric through a multistep dip coating process. The as‐prepared PMIA/AgNWs/PEDOT:PSS composite nonwoven fabric shows an electrical resistance as low as 0.92 ± 0.06 Ω sq−1 with good flexibility. The incorporation of the PEDOT:PSS coating layer improves the adhesion between AgNWs and PMIA nonwoven fabric, and also enhances the thermal stability of the composite nonwoven fabric. Electromagnetic interference (EMI) shielding and Joule heating performances of the PMIA/AgNWs/PEDOT:PSS composite nonwoven fabric are also investigated. The results show that the average EMI shielding effectiveness (SE) of the single‐layer nonwoven fabric in X‐band is as high as 56.6 dB and retains a satisfactory level of SE after being washed, bended, and treated with acid/alkali solution and various organic solvents. The composite nonwoven fabric also exhibits low voltage‐driven Joule heating performance with reliable heating stability and repeatability. It can be envisaged that the multifunctional PMIA/AgNWs/PEDOT:PSS nonwoven fabric with reliable stability and chemical robustness can be used in EMI shielding devices and personal thermal management products. [ABSTRACT FROM AUTHOR]

Thin‐film composite (TFC) forward‐osmosis (FO) membranes were developed on different woven and nonwoven backing fabrics as support. Embedded backing fabrics have a significant effect on the membrane film sublayer by imparting porosity, membrane mechanical strength, and thickness. Woven and nonwoven backing fabric supports have been used for FO membranes cast on the commercial scale. There are also a few studies on the laboratory scale, but repeating them seems to be a challenge. The results herein show that TFC membranes with nonwoven incorporated substrates gain a higher water flux while keeping the specific reverse salt flux low. [ABSTRACT FROM AUTHOR]

Ethnic value of many known plants are underexploited for medicinal application besides their proven traditional qualities. One such plant known for wound healing is Tridax procumbens. This plant has wound healing property and is commercially unexploited. Silver nanoparticle (Ag‐NP) were synthesized using this plant extracts using different solvents (methanol, ethyl acetate and aqueous), which exhibit resonance at 426, 424 and 418 nm, respectively. This plant‐mediated Ag‐NPs have strong anti‐bactericidal activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Streptococcus pyogenes, Klebsiella pneumonia, Serratia marcescens and Bacillus subtilis with methanol extract. Further instance, elemental composition was confirmed by energy dispersive X‐ray analysis and particle size ranges were observed at 80–200 nm with spherical shape nanoparticles by scanning electron microscopy and transmission electron microscopy analysis. The biocompatibility of Ag‐NPs was assessed using fibroblast cell line (L929) by MTT assay with 109.35 µg IC50 value. The oxygen plasma treated and non‐treated bamboo spunlaced nonwoven fabrics were coated with the Ag‐NPs by exhaust method. Contact angle and water retention revealed significant difference in absorption ability of plasma treated fabric. Field emission scanning electron microscopy revealed the presence of Ag‐NPs in plasma coated fabrics. The fabricated cloth was studied for anti‐microbial and microbial penetration ability. [ABSTRACT FROM AUTHOR]

Background: Oil pollution of water causes extensive damage to the environment and human health. Adsorption techniques are environmentally friendly and relatively feasible to treat oil contamination and reclaim oil resources, and it is essential to develop adsorbents that have high adsorption capacity for oil which can be recycled and regenerated conveniently to save money and resources. Results: Hydrophobic nonwoven fabrics coated with polydivinylbenzene nanofibres (HNF‐PDVB) were constructed by a one‐step cation polymerization reaction. The results showed that the optimal concentration of OTS (octadecylsilane) for the modification of nonwoven fibers was 1.22 mL L–1of n‐hexane. The HNF‐PDVB showed relatively good performance in adsorbing oil from water, with adsorption capacity as high as 7.5 g g–1. Freundlich and Dubinin–Radushkevic isotherms fitted well with the experimental data. The kinetic data fitted better to the pseudo‐second‐order and intraparticle diffusion models, and the parameters indicated that the adsorption by HNF‐PDVB involved macropores that contributed to the rapid and high‐capacity adsorption, as well as micropores that resulted in the diffusion of oil in the nanofibres. Thermodynamics studies revealed that the adsorption was spontaneous and endothermic, with an increasing performance when the temperature rose from 10 to 50 °C. The material possessed good stability and the adsorption capacity reduced from 7.5 g g–1 to 6.6 g g–1 after ten cycles of repeated use, recovered by squeezing and ethanol extraction. Conclusion: This work demonstrates that the new hydrophobic nonwoven fabrics have the potential to be used for elimination of pollution from oil wastewater. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: The theoretical analysis of the spunbond process was set up and applied to polypropylene (PP) and its blends. The effect of blending low tacticity polypropylene (LMPP) to high tacticity PP on the spinnability of the spunbond process was investigated. A small amount of LMPP was found to stabilize the high‐speed spinning of PP, and very fine fibers were obtained. From the calculated results, it was speculated that the improvement of spinnability originated from the suppression of crystallization speed and strain rate in the spinning process. The physical properties of the spunbond nonwoven fabrics were also investigated. [ABSTRACT FROM AUTHOR]

Abstract: In ligament reconstruction involving anterior cruciate ligament surgery, biological fixation between the transferred ligament and bone tissue is critical for achieving successful outcomes. Here, we administered chitin fabrics into the bone tunnels and evaluated their efficacy in promoting biological fixation. An animal model on the rat's patellar ligament was employed. First, bone tunnels were created in the lateral condyle of the femur. The ligament was then separated from the tibial tuberosity, and half was inserted into the tunnel and fixed with the use of end button. Animals in the experimental group were treated with microfiber nonwoven chitin fabric, whereas control animals received no treatment. Specimens were collected at 2, 4, and 6 weeks after surgery, and the fixation strength was measured by mechanical tests. Histological sections were prepared from samples prepared 4 weeks after surgery, and the diameter of bone tunnel and the width ratio of collagenous tissue in the bone tunnel were measured. Administration of chitin significantly increased the mean fixation strength at 4 and 6 weeks after surgery. Furthermore, chitin also promoted bone formation in the bone tunnel and increased the density of collagen fibers. Thus, microfiber nonwoven chitin fabric enhanced the biological fixation of the ligament to the bone tissue. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2355–2360, 2018. [ABSTRACT FROM AUTHOR]

ABSTRACT The effects of pure and impure magnetic nanoparticles (MPs) with three different concentrations (0.01, 0.1, and 1 wt %/v) on the morphological structure, crystallinity level, thermal properties and constituent interactions of electrospun poly(lactic acid) (PLA): poly(ε-caprolactone) (PCL)-based composites were investigated by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), and drug release tests using UV-vis spectrophotometry. Tetracycline hydrochloride (TCH), as a typical therapeutic compound, was loaded into these composite fibrous structures to study their application for drug delivery. The infrared spectra of composite nanofibers confirm the successful embedding of MPs into the fibrous networks. The addition of pure MPs increased the solution viscosity and thus promoted the MP dispersion inside the electrospun composite fiber mats. Impure MPs led to considerably lower average fiber diameters, and could generate unique cell structures that were reported for the first time in this study. The accelerated release of TCH was found by adding pure MPs to PLA:PCL blends. This characteristic was reflected in the parameters of Ritger-Peppas and Zeng models, which were well fitted to our experimental drug release data. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1607-1617 [ABSTRACT FROM AUTHOR]

The article reports on the use of dimensional analysis to quantify dimensionless indicators of the performance of fabric filters used in gas-cleaning applications. The authors allude to filtration indices proposed previously and a cleaning efficiency index derived using dimensional analysis. The authors experimented with the derived parameters and others used historically in air-pollution engineering in applications involving fly-ash aerosols and non-woven fabric filters. Results are said to demonstrate the utility of the parameters investigated in comparing the effectiveness of filter materials used in different gas-cleaning applications.

Biological fixation or anchorage of fibrous materials to bone by bone ingrowth into the spaces between fibers is a major concern in developing novel medical implants, including artificial ligaments. Toward this end, we evaluated the efficacy of chitin/chitosan as a bone formation accelerator. Specimens of polyester nonwoven fabric coated with chitin/chitosan were implanted into holes drilled into the distal ends of rat femora. Uncoated fabric specimens were used as controls. At 1 or 2 weeks after implantation, the specimens were retrieved, and the fixation strength was measured by mechanical testing. Histological sections of 2‐week implantation specimens were prepared, and the area of new bone tissue formed in the spaces between the fibers of the fabric was measured. The chitin/chitosan coating significantly increased the fixation strength and the area of bone tissue formed in the spaces between the fibers. The mean fixation strength of chitin/chitosan‐coated fabric specimens was more than twice that of the controls at 2 weeks after implantation. These results demonstrated that the chitin/chitosan coating effectively induced bone formation in the spaces between the fibers and enhanced biological fixation of the fibrous materials to the bone. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009 [ABSTRACT FROM AUTHOR]

The article discusses a study on the preparation and characterization of polypropylene non-woven fabrics prepared by melt-blown spinning process. Topics covered include the mechanical properties, contact angle, water flux, average pore size, average pore pressure, and particle removal efficiency of the fabrics, the treatment of the fabrics with heat and plasma processes, and the suitability of the fabrics for use as filtration membranes for wastewater purification.