Search Results (12)

The enzymatic hydrolysis process is important in the field of textile waste reuse in the circular economy context. Currently, enzymatic cellulase treatment of waste textiles, such as bamboo mixture with spandex samples (BS), cotton jeans (CJ), linen (L), and cotton T-shirts (CT), has been tested, in which glucose production was measured at the presence of 6 and 8% NaOH solution. The characteristics of the textiles and hydrolysis capacity were evaluated by the amount of glucose (g) obtained from each textile. The following indicators were also measured during the experiment: temperature, pH, enzymatic cellulase solution composition, final glucose concentrations, turbidity, and color intensity. The temperature of the mixture was maintained at 50 °C, and a pH level of 5–7 along with a contact time of 48–94 min were controlled. The experiments demonstrated that when the enzymatic hydrolysis was active, turbidity increased from 86 nephelometric turbidity unit (NTU) to >1000 NTU; the color of the hydrolyzed samples was obtained from 86 NTU to >1000 NTU; and the final glucose concentration was approximately between 0.49 and 33.9 mmol/L for L, CT, and CJ samples measured to produce up to one gram of glucose from 3.330 g of textile, and a BS samples produced one gram of glucose from 3.164 g of textile. The findings show that recycled glucose obtained from textile waste materials is environmentally sustainable. Such textile waste can then be reused rather than being dumped in already overloaded landfills. Full article

Wearable communication technologies necessitate antenna designs that harmonize ergonomic compatibility, reliable performance, and minimal interaction with human tissues. However, high specific absorption rate (SAR) levels, limited radiation efficiency, and challenges in integration with flexible materials have significantly constrained widespread deployment. To address these limitations, this manuscript introduces a novel wearable cavity-backed substrate-integrated waveguide (SIW) antenna augmented with artificial magnetic conductor (AMC) structures. The proposed architecture is meticulously engineered using diverse textile substrates, including cotton, jeans, and jute, to synergistically integrate SIW and AMC technologies, mitigating body-induced performance degradation while ensuring safety and high radiation efficiency. The proposed design demonstrates significant performance enhancements, achieving SAR reductions to 0.672 W/kg on the spine and 0.341 W/kg on the forelimb for the cotton substrate. Furthermore, the AMC-backed implementation attains ultra-low reflection coefficients, as low as −26.56 dB, alongside a gain improvement of up to 1.37 dB, culminating in a total gain of 7.09 dBi. The impedance bandwidth exceeds the ISM band specifications, spanning 150 MHz (2.3–2.45 GHz). The design maintains remarkable resilience and operational stability under varying conditions, including dynamic bending and proximity to human body models. By substantially suppressing back radiation, enhancing directional gain, and preserving impedance matching, the AMC integration optimally adapts the antenna to body-centric communication scenarios. This study uniquely investigates the dielectric and mechanical properties of textile substrates within the AMC-SIW configuration, emphasizing their practicality for wearable applications. This research sets a precedent for wearable antenna innovation, achieving an unprecedented balance of flexibility, safety, and electromagnetic performance while establishing a foundation for next-generation wearable systems. Full article

This study explores previous research efforts concerning prediction models related to the textile and polymer industry, especially garment seam strength, emphasizing critical parameters such as stitch density, fabric GSM, thread type, thread count, stitch classes, and seam types. These parameters play a pivotal role in determining the durability and overall quality of denim jeans based on cellulosic polymer. A significant focus is dedicated to the mathematical computational models employed for predicting seam strength in five-pocket denim jeans. Herein, the discussion poses the application of AI for manufacturing industries, especially for textile and clothing sectors, and highlights the importance of using a machine learning prediction model for sewing thread consumption, seam strength analysis, and seam performance analysis. Therefore, the authors suggest the significant importance of the machine learning prediction model, as future trends anticipate advancements in AI-driven methodologies, potentially leading to high-profile predictions and superior manufacturing processes. The authors also describe the limitation of AI and address a comprehensive model of risk outlines of AI in the manufacturing-based industries, especially the garments industry. Put simply, this review serves as a bridge between the realms of AI, mathematics, and textile engineering, providing a clear understanding of how artificial-neural-network-based models will be shaping the future of seam strength prediction in the denim manufacturing landscape. This type of evolution, based on ANN, will support and enhance the accuracy and efficiency of seam strength predictions by allowing models to discern intricate patterns and relationships within vast and diverse datasets. Full article

A coplanar-waveguide-type fed half-circular spike-shaped monopole antenna is designed on textile substrates and analyzed in this paper. The most suitable textile substrate is identified in this work by testing the current model performance characteristics on silk, jeans and cotton fabrics and is presented this analytical study. The cotton material model provided a bandwidth of 9.4 GHz, the silk material provided a 9.2 GHz bandwidth and the jeans material provided 9.1 GHz. A maximum gain of 9.5 dB was attained for 3.6 GHz of the 5G band and 8.2 dB for 5.8 GHz of the WLAN band. The antenna is prototyped on cotton substrate, bending analysis is also performed at 15 degrees, 30 degrees and 45 degrees in vertical and horizontal conditions and we find satisfactory results for the specified application. Compact, wearable antennas with varied performance are in demand as wireless communication systems evolve. The antenna is designed for wearable and textile-integrated wireless communication. The textile substrate makes the antenna flexible and can be integrated into garments, wearable gadgets and smart textiles. This paper describes how to choose textile materials and design a half-circular spike monopole antenna. Electromagnetic simulations evaluate the antenna’s impedance matching, radiation pattern and bandwidth. The CPW feedline is designed to efficiently transfer power to the antenna, improving performance. This study also examines the antenna’s longevity and resilience in textile materials, addressing real-world issues like bending and washing. This examination verifies the antenna’s wearable functionality and reliability. Full article

Indigo Blue (IB) is a dye widely used by the textile sector for dyeing cellulose cotton fibers and jeans, being considered a recalcitrant substance, and therefore resistant to traditional treatments. Several methodologies are reported in the literature for the removal or degradation of dyes from the aqueous medium, among which photoelectrocatalysis stands out, which presents promising results in the degradation of dyes when a dimensionally stable anode (DSA) is used as a photoanode. In the present work, we sought to investigate the efficiency of a Ti/RuO₂-TiO₂ DSA modified with tin and tantalum for the degradation of Indigo Blue dye by photoelectrocatalysis. For this, electrodes were prepared by the thermal decomposition method and then a physical–chemical and electrochemical analysis of the material was carried out. The composition Ti/RuO₂-TiO₂-SnO₂Ta₂O₅ (30:40:10:20) was compared to Ti/RuO₂-TiO₂ (30:70) in the photocatalysis, electrocatalysis, and photoelectrocatalysis tests. The photocatalysis was able to degrade only 63% of the IB at a concentration of 100 mg L⁻¹ in 3 h, whereas the electrocatalysis and photoelectrocatalysis were able to degrade 100% of the IB at the same initial concentration in 65 and 60 min, respectively. Full article

Circularity of cellulose-based pre- and post-consumer wastes requires an integrated approach which has to consider the characteristics of the fibre polymer and the presence of dyes and additives from textile chemical processing as well. Fibre-to-fibre recycling is a condition to avoid downcycling of recycled material. For cellulose fibres regeneration via production of regenerated cellulose fibres is the most promising approach. Textile wastes contain dyes and additives, thus a recycling technique has to be robust enough to process such material. In an ideal case the reuse of colorants can be achieved as well. At present nearly 80% of the regenerated cellulose fibre production utilises the viscose process, therefore this technique was chosen to investigate the recycling of dyed material including the reuse of the colorant. In this work, for the first time, a compilation of all required process steps to a complete circular concept is presented and discussed as a model. Indigo-dyed viscose fibres were used as a model to study cellulose recycling via production of regenerated cellulose fibres to avoid downcycling. Indigo was found compatible to the alkalisation and xanthogenation steps in the viscose process and blue coloured cellulose regenerates were recovered from indigo-dyed cellulose. A supplemental addition of reduced indigo to the cellulose solution was also found feasible to adjust colour depth in the regenerated cellulose to the level required for use as warp material in denim production. By combination of fibre recycling and indigo dyeing the conventional yarn dyeing in denim production can be omitted. Model calculations for the savings in water and chemical consumption demonstrate the potential of the process. The proportion of the substitution will depend on the collection rate of denim wastes and on the efficiency of the fibre regeneration process. Estimates indicate that a substitution of more than 70% of the cotton fibres by regenerated cellulose fibres could be achieved when 80% of the pre- and post-consumer denim wastes are collected. Therefore, the introduction of fibre recycling via regenerated cellulose fibres will also make a substantial impact on the cotton consumption for jeans production. Full article

Quickly changing fashion trends generate tremendous amounts of textile waste globally. The inhomogeneity and complicated nature of textile waste make its recycling challenging. Hence, it is urgent to develop a feasible method to extract value from textile waste. Pyrolysis is an effective waste-to-energy option to processing waste feedstocks having an inhomogeneous and complicated nature. Herein, pyrolysis of denim jeans waste (DJW; a textile waste surrogate) was performed in a continuous flow pyrolyser. The effects of adding sodium carbonate (Na₂CO₃; feedstock/Na₂CO₃ = 10, weight basis) to the DJW pyrolysis on the yield and composition of pyrolysates were explored. For the DJW pyrolysis, using Na₂CO₃ as an additive increased the yields of gas and solid phase pyrolysates and decreased the yield of liquid phase pyrolysate. The highest yield of the gas phase pyrolysate was 34.1 wt% at 800 °C in the presence of Na₂CO₃. The addition of Na₂CO₃ could increase the contents of combustible gases such as H₂ and CO in the gas phase pyrolysate in comparison with the DJW pyrolysis without Na₂CO₃. The maximum yield of the liquid phase pyrolysate obtained with Na₂CO₃ was 62.5 wt% at 400 °C. The composition of the liquid phase pyrolysate indicated that the Na₂CO₃ additive decreased the contents of organic acids, which potentially improve its fuel property by reducing acid value. The results indicated that Na₂CO₃ can be a potential additive to pyrolysis to enhance energy recovery from DJW. Full article

In this article, a novel frequency slot-based switchable antenna fabricated on flexible and nonflexible materials is presented for suitable reconfigurable radiations of Bluetooth, WiMAX, and upper WLAN applications. Initially, the performance of this structure was simulated using a CST^TM simulator and evaluated experimentally using a nonflexible FR4 structure. The same antenna was implemented on a flexible (jean) substrate with a relative permittivity of 1.7. The proposed textile antenna prototypes were fabricated by optimal dimensions of an E-shaped slot with a variation on the shape of the ground layer, integrated using a crossed T-shaped strip with ON/OFF switchable state operations. The proposed antenna prototype is compact (20 × 20 mm²), providing switchable radiations with tri bands, has frequencies ranged at 2.36–2.5 GHz for Bluetooth, 3.51–3.79 GHz and 5.47–5.98 GHz for the distinct bands of WiMAX and WLAN, respectively, as well as part of UWB operations. Full article

The development and study of a novel and very miniaturized ultra-wideband (UWB) wearable band-notch antenna for body sensor networks (BSNs) and mobile healthcare system have been presented in this paper. A very user-friendly and reliable software Computer Simulation Technology (CST)^TM Microwave Studio was used for the modeling and simulation purpose of this antenna. The antenna is a textile-based UWB notch antenna, as it was printed on jeans’ textile substrate. The simulated performance parameters, such as return loss, bandwidth, gain, radiation efficiency and radiation patterns of this antenna are demonstrated and analyzed. The main aim of this paper was to design a textile-based compact UWB antenna with the characteristics of band notch in X-band to reject the down link band (7.25 GHz–7.75 GHz) of satellite communication in the UWB frequency ranges of 3.1 to 10.6 GHz in order to avoid interference. The simulated results show that this antenna has very well band notch characteristics in the frequency range of 7.25–7.75 GHz. The overall dimension of the antenna is 25 mm in length and 16 mm in width, which is very compact. The antenna is printed on 1 mm Jeans’ textile with the dielectric constant of 1.7. This antenna shows very good results; it has compact size and is printed on textile material, and has band notch characteristics to avoid interference. Due to all these attractive characteristics, it will be a good candidate for body sensor networks for a mobile healthcare system. Full article

According to the Ellen MacArthur Foundation, 73% of used clothing is landfilled or incinerated globally and greenhouse gas (GHG) emissions from fabric manufacturing in 2015 amounted to 1.2 billion tons. It must be reduced in the future, especially by reusing and recycling used clothing. Based on this perspective, researchers calculated the energy consumption and GHG emissions associated with reusing and recycling used clothing globally with a life cycle assessment (LCA). However, no study was conducted so far to estimate the total GHG emission reductions in Japan by reusing and recycling used clothing. In this study, the amount of used clothing currently discharged from households as combustible and noncombustible waste and their fiber types were estimated using literature. Then, the methods for reusing and recycling of used clothing were categorized into the following 5 types based on fiber type, that is, “reuse overseas,” “textile recycling to wipers,” “fiber recycling,” “chemical recycling” and “thermal recycling.” After that, by applying LCA, the GHG emission reductions by above 5 methods were estimated, based on the annual discharged weights of each fiber type. Consequently, the total GHG emissions reductions by reusing and recycling 6.03 × 10⁸ kg of used clothing totally were estimated around 6.60 × 10⁹ kg CO_2e, to range between 6.57 × 10⁹ kg CO_2e and 6.64 × 10⁹ kg CO_2e, which depended on the type of “chemical recycling.” The largest contribution was “reuse overseas,” which was 4.01 × 10⁹ kg CO_2e corresponded to approximately 60% of the total reduction. Where, it was assumed that used clothing were exported from Japan to Malaysia which was currently the largest importing country. In this case, GHG emissions to manufacture new clothing in China, the largest country currently to export them to Japan, can be avoided, which are 29.4 kg CO_2e and 32.5 kg CO_2e respectively for 1 kg jeans and 1 kg T-shirts. Adding the GHG emissions for overseas transportation to this, on average, 32.0 kg CO_2e per kg of used clothing was reduced by “reuse overseas,” which was 19.6 times larger than GHG emissions by incineration, 1.63 kg CO_2e per kg, in which carbon neutrality for cotton was not counted. As the result, the total GHG emission reductions above mentioned, around 6.60 × 10⁹ kg CO_2e, corresponds to 70% of the GHG emissions by incineration of total household garbage in Japan. Full article

In this manuscript, an antenna on textile (jeans) substrate is presented for the WLAN, C band and X/Ku band. This is a wearable textile antenna, which was formed on jeans fabric substrate to reduce surface-wave losses. The proposed antenna design consists of a patch and a defected ground. To energize the wearable textile antenna, a microstrip line feed technique is used in the design. The impedance band width of 23.37% (3.4–4.3 GHz), 56.48% (4.7–8.4 GHz) and 31.14% (10.3–14.1 GHz) frequency bands are observed, respectively. The axial ratio bandwidth (ARBW) of 10.10% (4.7–5.2 GHz), 4.95% (5.9–6.2 GHz) and 10.44% (11.8–13.1 GHz) frequency bands are observed, respectively. A peak gain of 4.85 dBi is analyzed at 4.1-GHz frequency during the measurement. The SAR value was calculated to observe the radiation effect and it was found that its utmost SAR value is 1.8418 W/kg and 1.919 W/kg at 5.2/5.5-GHz frequencies, which is less than 2 W/kg of 10 gm tissue. The parametric study is performed for the validation of the proper functioning of the antenna. Full article

This work presents an alternative wearable tracking system based on a low-power wide area network. A complete GPS receiver was integrated with a textile substrate, and the latitude and longitude coordinates were sent to the cloud by means of the SIM-less SIGFOX network. To send the coordinates over SIGFOX protocol, a specific codification algorithm was used and a customized UHF antenna on jeans fabric was designed, simulated and tested. Moreover, to guarantee the compliance to international regulations for human body exposure to electromagnetic radiation, the electromagnetic specific absorption rate of this antenna was analyzed. A specific remote server was developed to decode the latitude and longitude coordinates. Once the coordinates have been decoded, the remote server sends this information to the open source data viewer SENTILO to show the location of the sensor node in a map. The functionality of this system has been demonstrated experimentally. The results guarantee the utility and wearability of the proposed tracking system for the development of sensor nodes and point out that it can be a low cost alternative to other commercial products based on GSM networks. Full article