http://www.itast.ir/ Journal of Textiles and Polymers en daily 1 Thu, 22 May 2025 00:00:00 +0330 Thu, 22 May 2025 00:00:00 +0330 http://www.itast.ir/article_251130.html The biomechanical response of the lower leg to external compression was investigated using a three-dimensional, subject-specific finite element model, with emphasis on the effect of soft-tissue mechanical properties on interface pressure distribution. A lower-leg anatomical model was reconstructed from computed tomography data, and two commercially available compression stockings, Medi and Sigvaris, with the same nominal compression class (23–32 mmHg), were mechanically characterized and incorporated into the model. The predicted interface pressures ranged from 34–47 mmHg at the ankle, 17–37 mmHg at the calf, and 16–27 mmHg at the sub-knee region. Validation against experimentally measurements using a Kikuhime pressure gauge yielded mean relative prediction errors of 15% for Medi and 20% for Sigvaris. Parametric simulations with soft-tissue Young’s moduli of 0.01, 0.02, and 0.03 MPa demonstrated that tissue stiffness substantially influenced both pressure magnitude and spatial uniformity. Reducing Young’s modulus by 66% decreased peak interface pressure by 12–18% and promoted a more uniform circumferential pressure distribution. Despite identical nominal compression classes, Medi and Sigvaris produced distinct pressure distributions, highlighting the role of stocking mechanical properties and anatomical geometry. These findings demonstrate that soft-tissue stiffness should be considered when evaluating compression stocking performance and support the use of finite element modeling for comparative and patient-specific analysis. http://www.itast.ir/article_247418.html This study explores the innovative development of electronic textiles, focusing on wearable textile-based antennas designed for advanced applications in healthcare, and fitness. In this study, a novel textile-based ISM band microstrip patch antenna was designed and modeled to work in the 2.4 GHz frequency. The woven fabrics by silver-coated nylon6 multifilament yarns was used to prepare the patch and ground of antenna. A key aspect of the designing process involves calculating the relative permittivity of the denim fabric used as substrate. Determining this value caused the optimization of the antenna’s performance in the 2.4 GHz, ISM band. Moreover, the Simulation Technology using CST software analyzed the suggested antenna performance. Key findings of proposed antenna include a return loss below -10 dB, a gain of 7 dBi, and a Specific Absorption Rate (SAR) of 0.154 W/kg. The SAR results reveal that the antenna complies with safety standard limits. These results demonstrate the antenna’s efficiency, safety, and suitability for future application in wearable technologies. http://www.itast.ir/article_247562.html The structural integrity of concrete slabs is a vital concern in civil engineering, necessitating innovative reinforcement and retrofitting techniques to ensure their long-term performance and resilience. This study explores the use of a novel two-dimensional braided glass/epoxy composite grid for retrofitting two-way reinforced-concrete slabs. Through comprehensive numerical analysis and experimental validation, the research aims to assess the effectiveness of this advanced reinforcement technique in enhancing the mechanical properties and stress distribution of retrofitted slabs. The finite-element modeling procedure was validated experimentally using an unretrofitted control slab and a slab retrofitted with a 50×50 mm braided composite grid. A Representative Volume Element (RVE) model is employed to simulate the braided composite grid, providing insights into its advantages and potential challenges. The findings demonstrate significant improvements in load-bearing capacity, energy absorption and overall durability, offering a promising solution for the rehabilitation of aging infrastructure. Within the investigated configurations, braided-grid retrofitting increased the ultimate load by up to 53.62%, with the maximum improvement obtained for the 105 mm-thick C35 slab strengthened using the 100×100 mm grid. This study contributes to the existing body of knowledge by highlighting the practical applications and benefits of incorporating braided composite grid in the retrofitting of concrete slabs. http://www.itast.ir/article_250857.html Weft knitted fabrics are a group of textiles that are used in the production of clothing, especially sportswear, due to the specific configuration of the thread in the form of a loop in the fabric and having elastic properties; Therefore, the examination of comfort characteristics of this category of textiles is of particular importance. In this regards,, in this study, four groups of rib weft knitted fabrics made of polyester/lycra was used, while the feeding amount of elastic yarns in these fabrics was different. In order to evaluate their comfort properties, features such as air permeability, water vapour permeability, thermal insulation properties, tensile and compressibility behaviour of these fabrics were measured and the effect of presence ratio of elastic thread in fabric on their comfort properties, was investigated. According to the results, due to the 50% rise of elasticity of the knitted fabric, the structure of the fabric becomes denser and the empty spaces in its structure decrease; therefore, properties such as water vapour permeability, air permeability, and heat resistance diminish about 40, 80 and 30%, respectively. On the other hand, as a result of increasing the proportion of elastic yarn in the fabric, the breaking force and elongation increase, while the initial modulus decreases. Moreover, by growing the feed amount of elastic thread in the fabric, the thickness of the fabric and the thickness recovery rise, however, its relative compressibility declines. http://www.itast.ir/article_251049.html Pressure injuries remain a significant healthcare concern due to their impact on patient outcomes and treatment costs. While advanced powered support surfaces may improve pressure redistribution and microclimate control, their cost and energy dependence can limit widespread implementation. This study evaluated two hybrid textile support surfaces (Spacer+W1 and Spacer+W2) and compared their body–interface pressure performance with conventional surfaces, including foam and standard hospital mattresses, gel pads, fluidized surfaces, and air mattresses. Both hybrid surfaces demonstrated lower interface pressure index values than foam and standard mattresses under the tested conditions, indicating improved pressure redistribution. Spacer+W1 and Spacer+W2 showed comparable performance, suggesting minimal influence of pile configuration on pressure outcomes. The double-layer spacer textile design may support heat and moisture dissipation, and the cotton top layer provides a skin-friendly contact surface. Although certain powered air systems exhibited lower pressure values, the hybrid surfaces demonstrated favorable overall performance among passive systems evaluated. These findings suggest that hybrid textile support surfaces may represent a promising passive option for pressure management. Further clinical studies are required to confirm long-term effectiveness in diverse patient populations. http://www.itast.ir/article_245957.html Nanofibrous scaffolds based on polyvinyl alcohol (PVA), gelatin (GE), and sodium alginate (SA) were fabricated by electrospinning and loaded with silver nanoparticles (Ag-NPs, 0.4 wt%) to develop antibacterial biomaterials. The optimal scaffold composition consisted of PVA/SA at a volume ratio of 70:30 and was crosslinked with citric acid (5 wt% of the total polymer content). The physicochemical properties of the fabricated scaffolds were characterized using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analysis, and water contact angle (WCA) measurements. FTIR analysis confirmed intermolecular interactions among the polymer components and successful incorporation of Ag-NPs within the crosslinked polymer network. SEM observations demonstrated the formation of continuous nanofibrous structures, with the optimized PVA/SA/Ag-NP scaffold exhibiting an average fiber diameter of 266 ± 44 nm. EDX mapping verified the presence and homogeneous distribution of Ag-NPs throughout the nanofibrous matrix without noticeable aggregation. The incorporation of hydrophilic polymers resulted in favorable surface wettability, with the optimized scaffold exhibiting a water contact angle of 37.8°. Antibacterial activity evaluated against Staphylococcus aureus and Escherichia coli demonstrated inhibition zone diameters of 3.4 mm. Scaffolds without Ag-NPs showed no detectable antibacterial activity, whereas Ag-NP-loaded scaffolds effectively inhibited bacterial growth. These results demonstrate that Ag-NP-loaded PVA/GE/SA nanofibrous scaffolds possess favorable physicochemical characteristics, surface wettability, and antibacterial activity, suggesting their potential as antibacterial biomaterials for future tissue engineering and regenerative medicine applications. However, further investigations involving mechanical characterization, biological evaluation, and silver-release studies are required to fully establish their biomedical applicability.