Search Results (11)

Para-aramid fibers, known for their remarkable strength and thermal stability, are frequently employed in protective textiles for military and aerospace applications. However, continuous exposure to ultraviolet (UV) radiation can damage their protective characteristics. This study analyzes the ultraviolet protection factor (UPF) and UV transmittance of woven fabrics produced from 30/2 Ne spun para-aramid yarns in the warp and 10 Ne core-spun yarns in the weft. The weft yarns consisted of three sheath fibers—para-aramid, meta-aramid, and polyester—in combination with different specialty core materials. The results show significant differences in UPF before and after UV exposure, with para-aramid sheaths giving the highest improvement. UV exposure caused structural changes in the fibers, resulting in increased UV protection, particularly in fabrics with para-aramid sheaths. This study concludes that the combination of para-aramid fibers with specific core materials significantly enhances UV protection, making them well-suited for applications in high UV exposure environments. Full article

In this paper, the usage of core-spun compound yarns in ballistic fabric to improve ballistic performance is considered, as with the use of core-spun compound yarns, the yarn friction inside the fabric is enhanced, and, therefore, the energy absorption capability of the fabric is expected to increase. Three types of fabric were developed and compared. F_a refers to a woven type made with 100% Kevlar^® filament yarns. F_b was woven with core-spun compound aramid yarns, which were made of Kevlar^® filament yarns spun with staple aramid fiber. F_c was woven with core-spun compound polyester yarns, which were made of Kevlar^® filament yarns spun with staple polyester fiber. There were two main purposes for comparing these types. The first was to confirm if the ballistic performance could be improved with the usage of core-spun compound yarns instead of pure filament yarns. The second was to investigate if different compositions of spun fiber would influence ballistic performance. The research results are positive and quite interesting. They show that the usage of core-spun compound yarn could indeed help to increase ballistic performance and that core-spun compound aramid yarns are better than core-spun compound polyester yarns in this function. The research was carried out using both ballistic tests and FEA models. Full article

Cotton and polyester fiber blends are commonly used to improve the aesthetic features of finished items. The denim industry’s growing need for polyester fiber aids in analyzing the performance of denim fabrics woven from rigid and stretched weft yarn combined with cotton and polyester. This study evaluates the weight, dimensional changes, stiffness, tensile and tearing strength, stretch, and comfort properties of denim fabric woven from cotton and polyester in various blended ratios. Here, Ne 14/1 (42 tex) 100% cotton warp yarn and Ne 18/1 (33 tex) weft yarns, consisting of 100% cotton, 75/25, 50/50, and 25/75 cotton/polyester (CO/PES) blends, as well as 100% polyester, were used to produce 3/1 Z twill denim fabric. The weft yarns were categorized into three groups: rigid, core-spun, and dual-core-spun yarns. Experimental results showed a higher polyester content in weft yarn, and denim fabrics’ tensile and tearing strength was improved, whereas fabrics’ weight loss, dimensional changes, and stretch properties were reduced. Furthermore, different statistical analyses were conducted to evaluate the type of weft yarn and blending ratio interaction and correlation with fabric properties. Additionally, a regression model was developed with the weft yarn type and blending ratio as independent variables to predict the fabric properties. Full article

A plantain pseudostem was harvested and processed on the same day. The process began with manually separating the sheaths (80.85%) and the core (19.14%). The sheaths were subjected to a mechanical shredding process using paddles, extracting 2.20% of lignocellulosic fibers and 2.12% of sap, compared to the fresh weight of the sheaths. The fibers were washed, dried, combed, and spun in their native state and subjected to a steam explosion treatment, while the sap was subjected to filtration and evaporation. In the case of the core, it was subjected to manual cutting, drying, grinding, and sieving to separate 12.81% of the starch and 6.39% of the short lignocellulosic fibers, compared to the fresh weight of the core. The surface modification method using steam explosion succeeded in removing a low proportion of hemicellulose and lignin in the fibers coming from the shims, according to what was shown by Fourier Transform Infrared Spectroscopy (FT-IR), Thermogravimetric Analysis (TGA), and Differential Scanning Calorimetry (DSC), achieving increased σ_max and ε from the tensile test and greater thermal stability compared to its native state. The sap presented hygroscopic behavior by FT-IR and the highest thermal stability from TGA, while the starch from the core presented the lowest hygroscopic character and thermal stability. Although the pseudostem supplied two types of fibers, lower lignin content was identified in those from the core. Finally, the yarns were elaborated by using the fibers of the sheaths in their native and steam-exploded states, identifying differences in the processing and their respective physical and mechanical properties. Full article

Three-component strain sensors based on helical auxetic yarn (HAY) structure were designed. HAYs comprise elastic core yarn, wrapped by the composition of multifilament Nylon 66 and conductive spun yarns with three different electrical resistance. The electromechanical behavior of samples was investigated. The cross-section of samples was studied to investigate the aerial density of conductive fibers at different strain ranges. The results indicated that gauge factors of HAY strain sensors significantly depend on the electrical resistance of the conductive component. Therefore, a new generation of efficient wearable textile-based strain sensors is introduced, based on the adjustable and flexible nature of the auxetic yarns. Full article

Stretch fabric provides good formability and does not restrict the movement of the body for increased tension levels. The major expectations of a wearer in an apparel fabric are a high level of mechanical comfort and good aesthetics. The prediction of shrinkage in stretch fabric is a very complex and unexplored topic. There are no existing formulas that can effectively predict the shrinkage of stretch fabrics. The purpose of this paper is to develop a novel model based on an artificial neural network to predict the shrinkage of stretch fabrics. Different stretch fabrics (core-spun lycra yarn) with stretch in the weft direction were manufactured in the industry using a miniature weaving machine. A model was built using an artificial neural network method, including training of the data set, followed by testing of the model on the test data set. The correlation of factors, such as warp count, weft count, greige PPI, greige EPI, and greige width, was established with respect to boil-off width. Full article

This study examined the perspiration absorption and drying characteristics of eco-friendly fiber-embedded fabrics with different yarn structures. The wicking and drying rates of fifteen fabrics made from quadrilobal PET, Lyocell, and bamboo fibers were measured using two evaluation methods and compared with the pore diameter and hygroscopic characteristics of the constituent fibers in the yarns. The sheath/core yarn structure played a vital role in improving the moisture absorption and drying properties of the eco-friendly fibers embedded in high-performance fabrics, which was partly affected by the hygroscopicity and non-circular cross-section of constituent fibers in the yarns. Superior perspiration absorption and drying properties among the various eco-friendly high-performance fabrics were observed in the quadrilobal PET/Lyocell sheath/core and quadrilobal PET/bamboo spun yarn fabrics. By contrast, the PET/Lyocell Siro-fil, bamboo spun, and hi-multi PET yarn fabrics exhibited inferior moisture absorption and drying properties. In particular, the evaluated results between transverse and vertical wicking measuring methods in absorption property showed a similar trend. In contrast, the drying property measured between the drying rate (min) at a steady state and the drying rate (g) at a transient state showed a different trend. Multiple regression analysis showed that the wicking property of the eco-friendly fiber-embedded fabrics was mainly related to the pore diameter, cross-sectional shape, and absorption property of the fibers in the yarns, and it was also highly associated with the drying characteristics of the fabrics. The market application of the sheath/core yarn structure using Lyocell and bamboo fibers with quadrilobal PET is available for producing eco-friendly fabrics that can contribute to environmental improvement and wear comfort related to the moisture absorption and fast-drying properties of the woven fabrics. Full article

In this study, stainless steel (SS) filaments are wrapped in Ge fibers to form core-spun yarns. The yarns along with 500 D polyester (PET) fibers undergo weaving, thereby forming functional woven fabrics. The experiment is composed of two parts:yarns and fabrics. The yarns are twisted with TPI of 8, 9, 10, 11, and 12, and then tested for tensile strength and tensile elongation. The yarns possess mechanical properties that are dependent on the TPI—the higher the TPI, the better the mechanical properties. The maximal mechanical properties occur when the core-spun yarns are made of 12 TPI where the maximal tensile strength is 5.26 N and the lowest elongation is 43.2%. As for the functional woven fabrics, they are made of Ge/SS core-spun yarns as the weft yarns and 500 D PET yarns as the warp yarns. The tensile strength, tensile elongation, negative ion release, electromagnetic interference shielding effectiveness (EMI SE), and air permeability tests are conducted, determining the optimal woven fabrics. The 12 TPI core-spun yarns provide the woven fabrics with the maximal tensile strength of 153.6 N and the optimal elongation at break of 10.08%. In addition, the woven fabrics made with 8 or 9 TPI core-spun yarns exhibit an optimal EMI SE of 41 dB, an optimal air permeability of 212 cm³/cm²/s, and an optimal release amount of negative ion of 550–600 ions/cc. The proposed woven fabrics have a broad range of applications, such as functional garments and bedding. Full article

Wool of mountain sheep, treated nowadays as a waste or troublesome byproduct of sheep husbandry, was used for the production of sound-absorbing materials. Felts of two different thicknesses were produced from loose fibres. Additionally, two types of yarn, ring spun and core rug, were obtained. The yarns were used for the production of tufted fabric with cut and loop piles. During the examinations, basic parameters of the obtained materials were determined. Then, according to standard procedure with the use of impedance tube, the sound absorption coefficient was measured, and the noise reduction coefficient (NRC) was calculated. It was revealed that felt produced from coarse wool exhibits high porosity, and its sound absorbing capacity is strongly related to the felt thickness. For thicker felt the NRC achieved 0.4, which is comparable with the NRC of commercial ceiling tiles. It was shown that the crucial parameter influencing the sound absorption of the tufted fabrics was the pile height. For both types of yarns, when the height of the pile was increased from 12 to 16 mm, the NRC increased from 0.4 to 0.42. The manufactured materials made from local wool possess good absorption capacity, similar to commercial products usually made from more expensive wool types. The materials look nice and can be used for noise reduction as inner acoustic screens, panels, or carpets. Full article

Their highly deformable properties make shape memory polymers (SMP) a promising component for the development of new compression garments. The shape memory effect (SME) can be observed when two polymers are combined. In here, polycaprolactone (PCL) and thermoplastic polyurethane (TPU) were melt spun in different arrangement types (blend, core-sheath, and island-in-sea), whereas the best SME was observed for the blend type. In order to trigger the SME, this yarn was stimulated at a temperature of 50 °C. It showed a strain fixation of 62%, a strain recovery of 99%, and a recovery stress of 2.7 MPa. Full article

Electromagnetic pollution interferes with electronic equipment in proximity and jeopardizes human health, which urges the development of electromagnetic interference (EMI) shielding materials. It is urgent to develop electromagnetic interference (EMI) shielding materials. However, the preparation of materials with superhydrophobicity, flame retardancy and EMI shielding properties is still challenging. In this study, we invented a core-spun yarn feeding device, which uses polysulfonamide (PSA) roving as a coating material and stainless steel wire as the core material to prepare a conductive core-spun yarn, which solves the problem of the wire having an easily exposed fabric surface. The finally prepared conductive fabric was subjected to Waterproof 2P hydrophobic treatment to form a superhydrophobic flame-retardant EMI shielding fabric. The results show that the hydrophobic treatment creates a thin film over the woven fabrics, and the contact angle of the fabric surface can reach 155°. The hydrophobic treatment will not damage the shielding effect and slightly increase the dB value. The average dB value of PSA-SS-1’ and PSA-SS-2’ are increased by 0.82 dB and 1.92 dB, respectively. When composed of conductive wrapped yarns for both the warp and weft yarns, the electromagnetic interference shielding effectiveness (EMI SE) of conductive fabrics is beyond 30 dB at 0–3000 MHz and the burnt depth is shorter than 40 mm. As for real applications, superhydrophobic/flame retardant/EMI SE fabrics can be used in a moist and complex environment with retaining conductivity and shielding effectiveness. Full article