SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Felt

144

One of the key reasons for the limited use of atmospheric pressure plasma (APP) is its inability to treat non-flat, three-dimensional (3D) surface structures, such as electronic devices and the human body, because of the rigid electrode structure required. In this study, a new APP system design-wearable APP (WAPP)-that utilizes a knitting technique to assemble flexible co-axial wire electrodes into a large-area plasma fabric is presented. The WAPP device operates in ambient air with a fully enclosed power electrode and grounded outer electrode. The plasma fabric is flexible and lightweight, and it can be scaled up for larger areas, making it attractive for wearable APP applications. Here, we report the various plasma properties of the WAPP device and successful test results showing the decontamination of toxic chemical warfare agents, namely, mustard (HD), soman (GD), and nerve (VX) agents.

Concepts: Vacuum tube, Human body, Gas, Atmospheric pressure, Diode, Textile, Chemical warfare, Felt

89

A need exists for artificial muscles that are silent, soft, and compliant, with performance characteristics similar to those of skeletal muscle, enabling natural interaction of assistive devices with humans. By combining one of humankind’s oldest technologies, textile processing, with electroactive polymers, we demonstrate here the feasibility of wearable, soft artificial muscles made by weaving and knitting, with tunable force and strain. These textile actuators were produced from cellulose yarns assembled into fabrics and coated with conducting polymers using a metal-free deposition. To increase the output force, we assembled yarns in parallel by weaving. The force scaled linearly with the number of yarns in the woven fabric. To amplify the strain, we knitted a stretchable fabric, exhibiting a 53-fold increase in strain. In addition, the textile construction added mechanical stability to the actuators. Textile processing permits scalable and rational production of wearable artificial muscles, and enables novel ways to design assistive devices.

Concepts: Cotton, Textile, Yarn, Knitting, Felt, Weaving, Electroactive polymers, Linen

29

Synthetic textiles can shed numerous microfibers during conventional washing, but evaluating environmental consequences as well as source-control strategies requires understanding mass releases. Polyester apparel accounts for a large proportion of the polyester market, and synthetic jackets represent the broadest range in apparel construction, allowing for potential changes in manufacturing as a mitigation measure to reduce microfiber release during laundering. Here, detergent-free washing experiments were conducted and replicated in both front- and top-load conventional home machines for five new and mechanically-aged jackets or sweaters: four from one name-brand clothing manufacturer (three majority polyester fleece, and one nylon shell with non-woven polyester insulation) and one off-brand (100% polyester fleece). Wash water was filtered to recover two size fractions (>333 μm and between 20 and 333 μm); filters were then imaged and microfiber masses were calculated. Across all treatments, the recovered microfiber mass per garment ranged from approximately 0 to 2 grams, or exceeding 0.3% of the unwashed garment mass. Microfiber masses from top-load machines were approximately 7 times those from front-load machines; garments mechanically aged via 24-hour continuous wash had increased mass release under the same wash protocol as new garments. When comparing to published wastewater treatment plant influent characterization and microfiber removal studies, washing synthetic jackets or sweaters as per this study would account for most microfibers entering the environment.

Concepts: Mass, Sewage treatment, Textile, Clothing, Felt, Laundry, Button

28

The pursuit of harmonic combination of technology and fashion intrinsically points to the development of smart garments. Herein, we present an all-solid tailorable energy textile possessing integrated function of simultaneous solar energy harvesting and storage, and we call it tailorable textile device. Our technique makes it possible to tailor the multifunctional textile into any designed shape without impairing its performance and produce stylish smart energy garments for wearable self-powering system with enhanced user experience and more room for fashion design. The “threads” (fiber electrodes) featuring tailorability and knittability can be large-scale fabricated and then woven into energy textiles. The fiber supercapacitor with merits of tailorability, ultrafast charging capability, and ultrahigh bending-resistance is used as the energy storage module, while an all-solid dye-sensitized solar cell textile is used as the solar energy harvesting module. Our textile sample can be fully charged to 1.2 V in 17 s by self-harvesting solar energy and fully discharged in 78 s at a discharge current density of 0.1 mA.

Concepts: Electric charge, Solar cell, Energy conversion, Textile, Solar energy, Solar power, Clothing, Felt

28

The ability of a fabric to transfer moisture is referred to as ‘wicking’, and an increase in this property may have benefits in terms of comfort as well thermoregulation. However, this phenomenon has not been studied in the context of sporting type activities. Therefore, the purpose of this study is to assess whether comfort, thermal physiological parameters and physical performance can be impacted by the garment that is utilized. 10 men (age: 27.5 ± 4.4; height: 169.3 ± 14.2cm; weight: 80.05 ±10.87kg) and 10 women (age: 26.8 ± 3.7; height: 166.6 ± 4.46cm; weight: 64.63 ± 4.49kg) volunteered to participate in the study. A within-group, crossover, counterbalanced design was utilized that included the Illinois Agility Run (IAR) as well as the Multi Stage Fitness Test (MSFT). The IAR was also performed whilst wearing protective padding. The protocol was completed on two occasions, once while wearing cotton © and again while wearing a polyester (P) garment. Questionnaires referring to sensations of various components of comfort were completed after each test. The P garment provided significantly (P ≤ 0.05) greater comfort in men and women following both the IAR and the MSFT. The P garment led to significantly (P ≤ 0.05) improved performance during the IAR in women. The P garment also provided significantly (P ≤ 0.05) greater body mass loss during the protocol in women. This study demonstrated dramatic increases in the comfort of polyester garments, including while using protective equipment. This study also discovered the influence of polyester garments on anaerobic tasks, as well as revealing dramatic sex differences, where women appear to be much more sensitive to the benefits of polyester garments. Strength and conditioning coaches should be aware of the dramatic impact of garment choice, in aerobic and aerobic tasks, particularly in women.

Concepts: Gender, Textile, Anaerobic exercise, Clothing, Felt, The Dramatics, High-visibility clothing, Temple garment

28

Bloodstain pattern analysis (BPA) is the investigation and interpretation of blood deposited at crime scenes. However, the interaction of blood and apparel fabrics has not been widely studied. In this work, the development of bloodstains (passive, absorbed and transferred) dropped from three different heights (500, 1,000, 1,500 mm) on two cotton apparel fabrics (1 × 1 rib knit, drill) was investigated. High-speed video was used to investigate the interaction of the blood and fabric at impact. The effect of drop height on the development of passive, absorbed and transferred bloodstains was investigated using image analysis and statistical tools. Visually, the passive bloodstain patterns produced on the technical face of fabrics from the different drop heights were similar. The blood soaked unequally through to the technical rear of both fabrics. Very little blood was transferred between a bloody fabric and a second piece of fabric. Statistically, drop height did not affect the size of the parent bloodstain (wet or dry), but did affect the number of satellite bloodstains formed. Some differences between the two fabrics were noted, therefore fabric structure and properties must be considered when conducting BPA on apparel fabrics.

Concepts: Statistics, Blood, Pattern, Pattern recognition, Bloodstain pattern analysis, Felt, Blood residue, Bloodstain

28

The evidential significance of car seat fibres has been investigated. Thirty six samples of car seat fabric were examined and the fibres catalogued according to their morphology and characteristics. The majority of car seat fibres were black or grey thick polyester fibres that were either dyed or pigmented. The MSP spectra produced were unlike those usually obtained from black or grey polyester fibres used in clothing. Tapings taken from car seats were examined for car seat fibres, various types were found showing that these fibres are expected to shed from the fabric albeit in low numbers, unless the vehicle is older. No fibres that matched the samples of the car seat fabric were found on the tapings of the car seats. One hundred garments were examined for car seat fibres, 10% of garments had populations of such fibres present and 41% had at least one car seat fibre present. None of these fibres matched the samples of the car seat fabric or those from the car seat tapings.

Concepts: Paper, Polyester, Textile, Aramid, Car seat, Clothing, Felt

27

Highly stretchable, actuatable, electrically conductive knitted textiles based on Spandex (SPX)/CNT (carbon nanotube) composite yarns were prepared by an integrated knitting procedure. SPX filaments were continuously wrapped with CNT aerogel sheets and supplied directly to an interlocking circular knitting machine to form the three-dimensional electrically conductive and stretchable textiles. By adjusting the SPX/CNT feed ratio, the fabric electrical conductivities could be tailored in the range of 870 to 7092 S/m. The electrical conductivity depended on tensile strain, with a linear and largely hysteresis-free resistance change occurring on loading and unloading between 0 and 80% strain. Electrothermal heating of the stretched fabric caused large tensile contractions of up to 33%, and generated a gravimetric mechanical work capacity during contraction of up to 0.64 kJ/kg and a maximum specific power output of 1.28 kW/kg, which far exceeds that of mammalian skeletal muscle. The knitted textile provides the combination of strain sensing and the ability to control dimensions required for smart clothing that simultaneously monitors the wearer’s movements and adjusts the garment fit or exerts forces or pressures on the wearer, according to needs. The developed processing method is scalable for the fabrication of industrial quantities of strain sensing and actuating smart textiles.

Concepts: Electrical conductor, Carbon nanotube, Electrical conductivity, Textile, Knitting, Clothing, Felt, Circular knitting

27

Herein, we demonstrate that a flexible, air-permeable, thermoelectric (TE) power generator can be prepared by applying a TE polymer (e.g. poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate)) coated commercial fabric and subsequently by linking the coated strips with a conductive connection (e.g. using fine metal wires). The poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) coated fabric shows very stable TE properties from 300 K to 390 K. The fabric device can generate a TE voltage output (V) of 4.3 mV at a temperature difference (ΔT) of 75.2 K. The potential for using fabric TE devices to harvest body temperature energy has been discussed. Fabric-based TE devices may be useful for the development of new power generating clothing and self-powered wearable electronics.

Concepts: Electricity, Energy, Thermodynamics, Device, Textile, Clothing, Felt, Spandex

27

A scaled-up fiber wet-spinning production of electrically conductive and highly stretchable PU/PEDOT:PSS fibers is demonstrated for the first time. The PU/PEDOT:PSS fibers possess the mechanical properties appropriate for knitting various textile structures. The knitted textiles exhibit strain sensing properties that were dependent upon the number of PU/PEDOT:PSS fibers used in knitting. The knitted textiles show sensitivity (as measured by the gauge factor) that increases with the number of PU/PEDOT:PSS fibers deployed. A highly stable sensor response was observed when four PU/PEDOT:PSS fibers were co-knitted with a commercial Spandex yarn. The knitted textile sensor can distinguish different magnitudes of applied strain with cyclically repeatable sensor responses at applied strains of up to 160 %. When used in conjunction with a commercial wireless transmitter, the knitted textile responded well to the magnitude of bending deformations, demonstrating potential for remote strain gauge sensing applications. The feasibility of an all-polymeric knitted textile wearable strain sensor was demonstrated in a knee sleeve prototype with application in personal training and rehabilitation following injury.

Concepts: Cotton, Textile, Yarn, Knitting, Felt, Strain gauge, Textile manufacturing, Gauge