Polyester Knit Research Articles

Screen-printed textile substrates’ suitability as a platform for electrochemical sensors’ construction

Electronic sensors are essential in applications like biosensors and fuel cells, providing rapid solutions for substance detection. Integrating electrochemical sensors into textiles offers advantages such as flexibility, comfort, and potential for wearable applications. This study explores the suitability of three textile substrates—100 % polyester knit mesh (S1), 100 % recycled polyester knit mesh (S2), and 50 % recycled polyester/50 % hemp fabric (S3)—for constructing screen-printed electrodes (SPEs). The goal is to develop a textile-based electrochemical sensor with a 3-electrode system (reference, auxiliary, and working electrode) using semi-automated screen printing. The electrochemical performance of two carbon inks, Elantas 9553 and DuPont BQ242, was evaluated to select the best working electrode (WE) ink. DuPont BQ242 was found most suitable for WE production, exhibiting quasi-reversible behavior and temperature stability. The electrochemical behavior of the textile-SPEs printed with DuPont BQ242 revealed that substrate S3 had superior properties, with higher peak currents (peak current ratio of 1.2) and smaller peak potential separation (602 n/V). Carbon Elantas 9553 was more sensitive to temperature changes (1 % variation) than the more stable DuPont BQ242 (0.03 % variation). The stability of the inks on substrates was examined using the 4-point probe method, highlighting excellent electrical stability under UV, high temperatures, cosmetics, and artificial sweat. The final textile-based SPE outperformed commercial SPEs, showing superior redox properties, with a peak potential separation (ΔEp) 56 % smaller and a relative standard deviation (RSD) of 1.58 % over 20 measurements. These textile-based SPEs present a valuable alternative to conventional rigid sensors, which are typically single-use and less durable.

A Study on Moisture Transport Properties of Polyester Knit Fabrics for Application in Textile Products

A Study on Moisture Transport Properties of Polyester Knit Fabrics for Application in Textile Products

Study on Moisture Management Properties of Cotton/Polyester Knitted Fabrics

Abstract Comfortability of a fabric is achieved by improving the moisture management behavior of the knitwear. In our study, the moisture management behavior of polyester and cotton fibers blended in 100:0, 50:50, and 0:100 ratios in four different structures such as single jersey, cross tuck, cross miss, and twill at two different loop lengths, 0.29 and 0.32 cm, were studied. Objective fabric tests were conducted to analyze the thermal properties of various knitwear. The results clearly proved that the knit fabric made of 100 % polyester has better moisture management behavior and a considerable level of comfort. Therefore, polyester can be applied to active sportswear fabrics. The structure of the fabric and the length of the loops in the fabric further affect the moisture management behavior. The cross-stitch 100 % polyester knit fabric with a loop length of 0.32 has excellent moisture management behavior, which provides excellent moisture management property compared with all other samples.

Design of Chitosan-Polyester Composites to Reduce Particulate Contamination of Washing Wastewater

In this research, the modification of different polyester structures (fabrics and knits) by the biopolymer chitosan was studied to evaluate the effects of the polyester structure and treatments on the particulate pollution of wastewater. The pristine polyester and the chitosan-polyester fabric and polyester knit composites were washed cyclically with standard ECE A detergent at 60 °C. The laser diffraction technique was used to characterize the particle size of the washing wastewaters from the 1–5, 6–10 and 1–10 wash cycles. In addition, the total solids (TS), total suspended solids (TSS), total dissolved solids (TDS), turbidity and chemical oxygen demand (COD) were also determined, according to standard procedures. The obtained results show the influence of the polyester fabrics and polyester knit structures and chitosan-polyester composites on the particle size distribution (PSD) in the washing wastewater. Differences in the values of the characteristic parameters, especially the span value and shape factor (k) of the individual curves, are visible, indicating the release of particles during the washing process. The experimental results show that the laser diffraction technique is suitable for characterizing the particle dimensions of the washing wastewater for different pristine polyester structures and chitosan-polyester composites. Modification with chitosan has been shown to provide potential protection against the release of microplastic particles into the environment.

3D Printing of Conductive Flexible Filaments for E-Textile Applications

Electronic textiles (e-textiles) can incorporate conductive materials at all levels of integration, from fibers to yarns to fabric itself. There are many ways to connect the textile elements to electronic components with interconnect mechanisms from mechanical gripping to welding, to gluing, to printing, to embroidery, knitting, and weaving. 3D printing method offers the possibility of creating flexible and stretchable interconnects for e-textiles applications. This study explored 3D printing of flexible conductive filaments on fabric to create interconnects for hard electrical components as well as transmission lines and switches for electronic textile applications. NinjaTek Eel and Palmiga TPU based conductive filaments were printed on polyester knit fabric. Electrical characterization measurements as well as visual and haptic analysis of printed samples were conducted. The results showed that TPU based flexible conductive filaments offer possibilities of direct 3D printing onto textiles for electronic textile applications.

Impact of varying lactate concentration in sweat on liquid moisture transmission behaviour of layered ensembles

The present study is focussed on the impact of change in the lactate concentration (43 mM and 22 mM) in sweat solution on liquid moisture transmission behaviour through the clothing. The sweat solution with higher concentration of lactate (43 mM) shows delayed wetting at the top surface both in case of individual layer and multi-layer fabric ensembles, i.e. it takes longer time to wet the top surface in spite of the lower contact angle made by it. Significant difference is observed in in-plane transmission behaviour of both the sweat solutions in the case of multi-layered ensembles. In case of multi-layered ensembles, wetting time reduces drastically, even though both the ensembles consist of polyester knit as the inner surface possessing wetting time is 50 s approximately. Sweat solution with higher lactate concentration also shows higher cross-planar transmission rate as compared to in-plane transmission. Uni-directional seamed multi-layered spacer fabric exhibits better overall moisture management coefficient as compared to bi-directional seamed spacer ensembles with sweat solution containing higher lactate concentration. Middle layer also plays a vital role in altering the overall liquid moisture transmission behaviour.

High-quality and easy-to-regenerate personal filter.

Proper respiratory tract protection is the key factor to limiting the rate of COVID-19 spread and providing a safe environment for health care workers. Traditional N95 (FFP2) respirators are not easy to regenerate and thus create certain financial and ecological burdens; moreover, their quality may vary significantly. A solution that would overcome these disadvantages is desirable. In this study a commercially available knit polyester fleece fabric was selected as the filter material, and a total of 25 filters of different areas and thicknesses were prepared. Then, the size-resolved filtration efficiency (40-400 nm) and pressure drop were evaluated at a volumetric flow rate of 95 L/min. We showed the excellent synergistic effect of expanding the filtration area and increasing the number of filtering layers on the filtration efficiency; a filter cartridge with 8 layers of knit polyester fabric with a surface area of 900 cm2 and sized 25 × 14 × 8 cm achieved filtration efficiencies of 98% at 95 L/min and 99.5% at 30 L/min. The assembled filter kit consists of a filter cartridge (14 Pa) carried in a small backpack connected to a half mask with a total pressure drop of 84 Pa at 95 L/min. In addition, it is reusable, and the filter material can be regenerated at least ten times by simple methods, such as boiling. We have demonstrated a novel approach for creating high-quality and easy-to-breathe-through respiratory protective equipment that reduces operating costs and is a green solution because it is easy to regenerate.

Retention and release of odorants in cotton and polyester fabrics following multiple soil/wash procedures

Odorous clothing can be an annoying and unpleasant problem, particularly when odorants are not effectively removed via laundering. Cotton and polyester knit fabrics were soiled with three selected odorants, representing different polarities and lipophilicities (i.e. octanoic acid, 2-nonenal, dodecane). Fabrics were subjected to 1, 5 and 10 soil/wash cycles using a regular liquid detergent (Tide® Free and Gentle) or a sport liquid detergent (Tide® Plus Febreze Sport). Odorants released into the headspace were collected using solid phase micro-extraction, and odorants retained within the fabric were collected using solvent extraction. Analysis of odorant peaks was carried out using gas chromatography-flame ionization detection. Prior to laundering, higher amounts of all odorants were released into the headspace above polyester fabrics than above cotton fabrics. Cotton fabrics retained more octanoic acid within the fabric and lower amounts of 2-nonenal than polyester. Laundering was more effective at removing odorants from cotton than from polyester, and the polar octanoic acid was more readily removed than the two non-polar odorants from both fabrics. Accumulation of odorants occurred as soil/wash cycles increased from 1 to 5 cycles. However, between 5 and 10 soil/wash cycles the amounts of compounds did not significantly increase, with significantly lower amounts of octanoic acid extracted from cotton at 10 cycles compared to 5 cycles. The results from this study indicate that incomplete removal of odorants during washing, especially from oleophilic polyester fabrics, is a cause for odor build-up in clothing.

Characterization of Insect Stains Deposited by Calliphora vicina (Diptera: Calliphoridae) on Shirt Fabrics.

Despite the fact that necrophagous flies are known to alter bloodstains and create unique artifacts, no research has occurred to date that has examined the characteristics of insect stains on textiles or fabrics. This study represents the first effort to characterize artifacts produced by adult Calliphora vicina Robineau-Desvoidy deposited on a range of shirt fabrics that varied in type, color, orientation, and yarn tension. In general, artifact morphology on any type of fabric was distorted in comparison to those observed on smooth and/or nonporous surfaces in previous studies. Consequently, distinction of artifact type could only be made broadly as digestive artifacts and transfer patterns, in which the latter was predominantly detected as tarsal tracks. None of the artifacts displayed satellite stains typical of human bloodstains found on textiles. Wicking was evident on all fabrics but was most pronounced with dri wick and jersey knit polyester in comparison to cotton knit. Digestive artifacts on any colored fabric, but especially with green and yellow shirt samples, resembled the reported color, size, and morphology of bloodstains generated in laboratory studies on a range of fabrics. Unique digestive artifacts were also detected as small, black, and nearly spherical. These defecatory stains did not appear to wet or wick into any of the fabrics. Digestive artifacts and tarsal tracks differentially interacted with front face stitch loops of clothing fabrics to yield distinct stain patterns. The implications of these observations in reference to bloodstain pattern analysis at crime scenes are discussed.

Do Recycled Cotton or Polyester Fibers Influence the Shedding Propensity of Fabrics during Laundering?

Fabric shedding during laundering is detrimental to the longevity of clothing textiles, and in the case of non-biodegradable, synthetic fabrics, it is a source of diffuse microplastic fiber pollution. Textile recycling offers numerous economic and environmental benefits; however differences in fabric shedding due to their recycled fiber contents are relatively unknown. Accelerated laundering experiments were conducted to quantify the shedding propensity and characteristics of cotton knit, polyester knit, and twill weave fabrics, each at three differing recycled fiber contents. The 70% recycled polyester shed significantly fewer microfibers than the 40% recycled polyester. No other significant influences of recycled fiber content on shedding propensity were identified. The mean length of shed fibers from the 70% recycled polyester was significantly higher than that of the virgin polyester and the 40% recycled polyester.

Characterization and effect of atmospheric corona plasma on grey knit polyester fabric

The use of chemical compounds in dyeing is still dominant. This results in the redundant use of water for the washing. Therefore, there needs to be a research on an alternative method. This research is aimed at understanding the effect of both positive and negative corona plasma irradiations on fabric. It is expected that characteristics of voltage, current, and electrode spacing, as well as ion mobility from the corona plasma will be known, both for with and without grey polyester knit fabric. Other than that, dampness characteristics of the grey polyester knit fabric will also be known. Plasma discharge is generated using point-plane electrode configuration connected to a high voltage DC power supply. The number of point electrodes is 100. Meanwhile, irradiation on the fabric is performed by putting the grey polyester knit on top of the plane electrode. Characterization was then carried out by varying the voltage, spacing of both point and plane electrodes, with and without the fabric. Other than that, variation was also made for the duration of grey polyester knit fabric irradiation. The next step was water drop test to observe 1 mL water absorption on the grey polyester knit. Results show that adding potential difference increases the current of corona spark plasma discharge for both positive and negative current corona discharges. The same case was also observed when the plasma discharge was irradiated on the plane electrode, either with or without the grey polyester knit fabric. The presence of grey polyester knit altered discharge mobility in that the small spacing of the fabric increases mobility for both negative and positive corona discharge. Hence, the further the electrodes spacing, the less mobile charge particles become. Results of water drop test show that longer irradiation on the fabric speeds up water absorption in the grey polyester knit fabric, both for positive and negative corona irradiations.

Toxicity and environmental impacts approached in the dyeing of polyamide, polyester and cotton knits

Three colouration process was analyzed, in which consumption of water, the spent of electrical and thermal energy, emission of carbon dioxide besides effluent toxicity of dyeing of polyamide, cotton and polyester knits were approached. the dyeing of polyamide knit presented lowest consumption of electrical energy, the dyeing of polyester knit presented the lowest consumption of thermal energy and emission of co2 molecules into atmosphere, and the effluent of cotton dyeing presented lowest acute toxicity (CE50) to Daphnia similis.

Inkjet Printing of Reactive Silver Ink on Textiles.

Inkjet printing of functional inks on textiles to embed passive electronics devices and sensors is a novel approach in the space of wearable electronic textiles. However, achieving functionality such as conductivity by inkjet printing on textiles is challenged by the porosity and surface roughness of textiles. Nanoparticle-based conductive inks frequently cause blockage/clogging of inkjet printer nozzles, making it a less than ideal method for applying these functional materials. It is also very challenging to create a conformal conductive coating and achieve electrically conductive percolation with the inkjet printing of metal nanoparticle inks on rough and porous textile and paper substrates. Herein, a novel reliable and conformal inkjet printing process is demonstrated for printing particle-free reactive silver ink on uncoated polyester textile knit, woven, and nonwoven fabrics. The particle-free functional ink can conformally coat individual fibers to create a conductive network within the textile structure without changing the feel, texture, durability, and mechanical behavior of the textile. It was found that the conductivity and the resolution of the inkjet-printed tracks are directly related with the packing and the tightness of fabric structures and fiber sizes of the fabrics. It is noteworthy that the electrical conductivity of the inkjet-printed conductive coating on pristine polyethylene terephthalate fibers is improved by an order of magnitude by in situ heat-curing of the textile surface during printing as the in situ heat-curing process minimizes the wicking of the ink into the textile structures. A minimum sheet resistance of 0.2 ± 0.025 and 0.9 ± 0.02 Ω/□ on polyester woven and polyester knit fabrics is achieved, respectively. These findings aim to advance E-textile product design through integration of inkjet printing as a low-cost, scalable, and automated manufacturing process.

Artificial lightning strike tests on PRSEUS panels

The lightning damage resistance of Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) panels was characterized experimentally. Two unprotected PRSEUS panels were subjected to standard impulse current waveforms (consistent with actual lightning strikes) with 50, 125, and 200 kA nominal peak currents at a variety of panel locations. Lightning-induced damage to the PRSEUS panels was a strong function of (1) the peak current, (2) the lightning attachment location (mid-bay, stringer, frame, etc.) that involved different through-thickness Vectran™ stitching, and (3) the presence of a surface finish paint.The sizes of the damaged regions increased as the peak current increased, since greater peak current leads to more Joule heating. The lightning-damaged PRSEUS panels exhibited unique damage features due to the presence of through-thickness Vectran™ stitches and warp-knitted fabrics. Through-thickness Vectran™ stitches constrained the development and spread of intense local damage in the vicinity of the lightning attachment point. The polyester warp-knit threads used to stitch the warp-knitted laminates together appeared to influence the development of widespread small-scale fiber damage in the region surrounding the strike. Consequently, the Vectran™ structural stitches, as well as the polyester knit threads holding the tows together, have a significant beneficial effect on both the size of the impingement region and the subsequent damage propagation within the laminate. In addition, damage to the painted panel was greater for each current level than for the sanded (unpainted) panel.

Preparation and Application of Polymer-Composited Yarn and Knit Containing CNT/Ceramic

The properties and light-heating function of a knit prepared by the composite spinning of carbon nanotubes (CNTs) and an inorganic ceramic were examined. The CNTs and ceramic were mixed and polymerized in a master batch (MB) and the MB chip was then melt spun to prepare the CNT/ceramic-composite yarn (LH-Yn) and single-jersey knits (LH-Knit). The properties of the LH-Yn and LH-Knit were compared with those of the regular polyester yarn (PET-Yn) and polyester knit (PET-Knit). The contents of carbon in the CNTs by energy dispersive X-ray spectrometer, scanning electron microscopy, tensile and tear performance, thermal insulation, air permeability (AP), water vapor permeability (WVP), and far-infrared (FIR) emissivity were analyzed. The result showed that the surface temperature of the LH-Knit was much higher than that of the PET-Knit. The measured WVP, AP, and FIR emissivity were also slightly higher in the LH-Knit, but the difference was not significant.

Design of wearable hybrid generator for harvesting heat energy from human body depending on physiological activity

We developed a prototype of a wearable hybrid generator (WHG) that is used for harvesting the heat energy of the human body. This WHG is constructed by integrating a thermoelectric generator (TEG) in a circular mesh polyester knit fabric, circular-shaped pyroelectric generator (PEG), and quick sweat-pickup/dry-fabric. The fabric packaging enables the TEG part of the WHG to generate energy steadily while maintaining a temperature difference in extreme temperature environments. Moreover, when the body sweats, the evaporation heat of the sweat leads to thermal fluctuations in the WHG. This phenomenon further leads to an increase in the output power of the WHG. These characteristics of the WHG make it possible to produce electrical energy steadily without reduction in the conversion efficiency, as both TEG and PEG use the same energy source of the human skin and the ambient temperature. Under a temperature difference of ∼6.5 °C and temperature change rate of ∼0.62 °C s−1, the output power and output power density of the WHG, respectively, are ∼4.5 nW and ∼1.5 μW m−2. Our hybrid approach will provide a framework to enhance the output power of the wearable generators that harvest heat energy from human body in various environments.

Surface modification of knit polyester fabric for mechanical, electrical and UV protection properties by coating with graphene oxide, graphene and graphene/silver nanocomposites

In this paper, we study the elaboration method of knit polyester fabrics coated respectively, with graphene oxide, graphene and graphene/silver nanoparticles using a cost-effective and scalable approach. This coating approach allows for uniform deposition and good adhesion as well as low, diffuse reflectance. Interestingly, the treated fabrics demonstrate good flexibility, stretchability and foldability, while maintaining lightweight and durability. In addition, PES-G (polyester coated by graphene) and PES-G/Ag° (polyester coated by graphene/silver nanoparticles) exhibit uniform low electrical resistivity because of conductive network of graphene nanosheets and silver nanoparticles formed on the surface of polyester fabrics. Furthermore, the incorporation of low amount of silver nanoparticles into fabrics coated graphene exhibit high flexibility as well as UV blocking properties compared with those coated graphene oxide and graphene. Therefore, the results of this study confirm for the first time that silver nanoparticles and graphene coated into polyester fabric can be obtained with high mechanical and UV protection performances using simple approach. These promising results support the idea that the present approach is useful for the fabrication of flexible, stretchable, conductive and UV protector fabrics for diverse applications because of its low cost, large-scale process and compatibility.

Massive Incisional Hernia Repair with Parietex: Monocentric Analysis on 500 Cases Treated with a Laparoscopic Approach.

The aim of this retrospective study is to demonstrate the safety and feasibility of the laparoscopic technique for treatment of massive incisional hernias (MIHs) and to compare three different fixation devices. From January 1, 2001, to December 31, 2014, we collected retrospective data from patients with large incisional hernias (IHs). Laparoscopic IH repair is performed by applying a three-dimensional polyester knit structure mesh with a resorbable collagen barrier on peritoneal side (Parietex™ Composite Mesh; Covidien, New Haven, CT). Patients were divided into three groups according to the different fixation devices. The mean follow-up was 19 (12-156) months. The mean defect size was 12.83 cm (10-26 cm) and the mean body mass index was 30.8 kg/m2 (26-39 kg/m2). The EMS stapler™ was used on 260 patients, the Protack® on 210 patients, and the AbsorbaTack™ on 30 patients. The mean operative time was 69.9 minutes (38-130 minutes). Intraoperative morbidity rate was 1.6% (8 cases). Early reoperation rate was 0.2% (1 case). The mean length of hospital stay was 2.3 days (range 2-7 days). Seromas were observed in 20 patients (4.0%) and neuralgia in 10 patients (2.0%). Recurrence was observed in 12 patients (2.4%) with the majority in the absorbable tack group (10%). There were no conversions (0%) to open technique. The laparoscopic approach seems to be safe and appropriate for treatment of MIH. The Parietex composite mesh we used guarantees excellent intraabdominal laparoscopic repair of abdominal wall defects. Absorbatack system seems to give less postoperative neuralgia, but it is related to a high recurrence rate. Protack system seems to give more postoperative neuralgia than the Endopath EMS. In our experience, the best fixation system is the latter.

Development of flexible sensors using knit fabrics with conductive polyaniline coating and graphite electrodes

ABSTRACTThe aim of this study was to develop flexible sensors with cotton and polyester knit fabrics as substrates coated with polyaniline (PAni) doped with hydrochloric acid or phosphoric acid. The deposition of PAni onto the knit, polymerization synthesis, and doping of the aniline monomer were performed via an in situ reaction. Graphite dispersion was used to obtain the electrodes of the sensors, which were prepared differently for each substrate. The main evaluation of the sensors was carried out in a humidity chamber under nitrogen (N2) with the application of drying and wetting cycles. Significant differences were observed in the responses of the sensory devices to humidity, according to the dopant and substrate types. In all tests, the sensor response to variations in the ambient conditions was very good, with a rapid response to changes in the relative humidity, a good sensitivity (up to 34%), and a high reversibility (ca. 70–100%). © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44785.

Assessment of thermal comfort of nanosilver-treated functional sportswear fabrics using a dynamic thermal model with human/clothing/environmental factors

The development of nanotechnology has made it possible to add desirable functions to fabrics. Nanosilver has been used to provide antibacterial and odor control functions for sportswear over decades. However, few studies have explored the thermal comfort and ultraviolet (UV) protection properties of nanosilver-treated sportswear fabrics. In this study, a dynamic thermal model was introduced to predict the thermal comfort of nanosilver-treated fabrics for wearers in different environmental conditions. Nanosilver was applied to cotton and polyester knit fabrics and their antibacterial and UV protection properties were evaluated as well. The results indicated that substantial antibacterial and UV protection properties were achieved from nanosilver-treated fabrics. The dynamic thermal model predicted the thermal comfort of the treated fabrics for various human, clothing, and environmental factors. Although there was between two and four times difference in the thermal and evaporative resistance between the two tested fabrics, the predicted thermal comfort sensations were not significantly different in the same human and environmental conditions. From these results, it can be concluded that nanosilver-treated fabrics may provide desirable functionality, while not detracting from thermal comfort. This is one of the first trials in which a dynamic numerical thermal model was used to predict the thermal comfort of nanosilver-treated fabrics for sportswear, taking human, clothing, and environmental conditions into consideration.