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In this paper, biaxial warp-knitted flexible composites (BWFS) were fabricated with high tenacity polyester and PU film. The mechanical properties of the above BWFS samples are tested, including their tensile performance (in 0 °, 45 ° and 90 ° directions), tearing performance (in both 0 ° and 90 ° directions) and stabbing resistance. The results show that the tensile stress firstly decreases and then increases form 0 ° to 90 ° directions and the damage process of composite under uniaxial loading can be divided into three stages. The vertical tearing stress of all BWFS was almost higher than the horizontal tearing stress. In addition, the peak load and deformation displacement of the composites increase with an increase of high tenacity polyester fineness and inserted yarns density in stabbing resistance.

The main goals of this study were to determine the effect of three yarn structural factors (yarn count, cross section and spandex ratio) and their interactions on tensile and breaking extension properties tensile behavior effect of spandex/polyester spun yarns respective on woven fabrics. Moreover, stress-strain curves were plotted and the yield points and breaking points and their corresponding properties (toughness, stiffness and Initial Young Modulus) were derived. The association between tensile and elongation parameters for spandex/polyester yarn and their woven fabrics was computed using simple correlation coefficient, results explained that all tensile and breaking extension properties significantly increased as the yarn count increased while the effect of cross section was weak or marginal. It is obvious that yield strain, yield stress, breaking extension, breaking tenacity decreased as a result of increasing the spandex content but the decrease percents (%) were generally weak. With respect to the 1st and 2nd order interaction effects, they were no significant for most tenacity and elongation properties of spandex/polyester spun yarns and their respective woven fabrics. The current study appeared that using spandex/polyester spun yarns with lowest spandex content gave the best tensile and breaking extension properties of spandex/polyester spun yarns and their respective woven fabrics. The correlation coefficients between tensile and elongation parameters for spandex/polyester yarn and their corresponding woven fabrics were positive and highly significant (except Initial Young's modulus) indicating that the tensile and breaking extension properties of the spandex/polyester yarns could be used as good indicators for the strength and elongation of fabrics manufactured by these spandex/polyester yarns.

PurposeOccurrence of fabric rupture is a problem that can influence fabric performance during wear. In this regard, fabric tearing resistance is considered by manufacturers and consumers and enhancing tear resistance through optimization of related parameters is beneficial.Design/methodology/approachIn this study, the tearing resistance of a series of shirting fabrics with various weave patterns and weft densities were investigated by both static and dynamic tear test methods. Moreover, the constituent yarn's frictional and tensile behaviour was evaluated and their relation with tear resistance was analysis.FindingsAccording to the outcomes, the fabric firmness and density and friction of yarns affect the tear resistance, reversely. However an improvement in yarn's tenacity can raise the tear resistance.Originality/valueIn this study it was aimed to not only consider influence of both static and dynamic tear test approach on the tearing performance of fabrics regarding their structural parameters, the impact of the constituent's yarn properties include tensile behaviour and friction coefficient on the tearing performance of fabric considered, as well.

The development of tenacity photoluminescent (PL) hydrogels is very great significance to promote the application of optical technology in hydrogel. Herein, we report a high-toughness PL hydrogel that combines synthetic hydrophilic lanthanide complex (LCs) and tannic acid (TA) with polyvinyl alcohol (PVA) by frozen-thawing. The resulting hydrogel has high mechanical strength (1194.46-kPa tensile strength, 1266.17-kJ m−3 toughness energy, 1915.58-kPa compressive strength, and 269.79-kJ m−3 energy dissipation at 80% compression), excellent self-recover and anti-fatigue performance, good photoluminescence, and switchable functions under UV light, showing red (254 nm) and green (365 nm), respectively. The design strategy offers a new approach for the preparation of multifunctional and tenacity PL hydrogels.

Technology for the transformation of waste feathers to quality regenerated filaments has been developed. Regardless of superior properties of natural keratin materials, previously developed regenerated materials from keratin had tensile properties much lower than their natural counterparts due to backbone hydrolysis and inefficient reconstruction of disulfide crosslinkages. In this work, tough keratin filaments have been regenerated from white duck feathers via efficient restoration of disulfide crosslinkages using a dithiol reducing agent. Dithiol substantially reserves free thiol groups in the extraction and formed lengthy intermolecular crosslinkages in regenerated keratin filaments. Due to the high degree of intermolecular reconstruction of disulfide bonds and formation of lengthy crosslinkages via dithiol chain-extension, the keratin filaments exhibited considerable improvements in mechanical properties, especially for ductility and water stability. The tenacity and elongation at break were 160.7 MPa and 14%, respectively. The filaments retained about 80% of the tenacity of natural feathers at either dry or wet conditions and demonstrated stretchability 150% higher than natural feathers. The fiber regeneration technology makes it possible to substitute primary fiber sources by renewable poultry feathers. Successful filament substitution or addition can bring more than 88-billion-dollar revenue. The technology not only contributes to a sustainable fiber and poultry industry but adds substantial values to poultry feathers.

Stinging nettle (Girardinia diversifolia) is a cellulosic plant fiber which is abundantly available in the upper regions of Himalayas. The stem fibres are pliable which are used to weave or knit fabric. This fiber is very strong, but rigid and inextensible. This has restricted its usage in handmade textile products only. In order to process this fiber on a range of textile machines for development of a variety of products with enhanced performance, the fiber needs to be strong, flexible and extensible. This study was aimed at to increase the fiber tenacity by giving chemical pre-treatment. The effects of various experimental parameters, such as chemical concentration and time on tenacity of nettle fibres were studied. In the study, the chemical pre-treated nettle fibers were examined for their mechanical characteristics and compared to untreated fibers (control sample). The untreated fiber was less flexible and less extensible. A pre-treatment resulted in increase in tenacity and elongation at break. The increase in tensile strength was found to be 5.46 g/den from 3.84 g/den (as in case of control sample) and elongation increased to 3.33% from 1.66%.

In this research work, the authors have investigated the influence of fibre orientation on thickness and tenacity of needle-punched nonwoven fabrics by using three-factor three-level Box–Behnken Design. Three carding parameters such as feeder speed, cylinder speed and doffer speed, which are primarily responsible for fibre orientation, were considered as three factors with three different levels. Fibre orientation was evaluated in terms of anisotropy by using tracer fibre technique. Anisotropy was measured in both un-punched and punched fibrous structure. Tenacity was measured in both machine and cross directions. It was found that the tenacity in the cross direction and thickness decreases but the tenacity in the machine direction increases with the increase of anisotropy as well as fibre orientation.

Melange cotton yarns possess unique attributes of aesthetics and comfort. The quality of melange yarn is largely influenced by fibre properties, spinning process, dyeing conditions and proportion of grey and dyed fibres. In this study, dyed and grey cotton fibre components were mixed at the blow room to produce melange yarns with three different shade depths. The aim of present work is to investigate the effect of raw material properties and process variables at different shade depths on the properties of cotton melange yarns. Box–Behnken experimental design was used to study effect of three factors: fineness of cotton, noil extraction% and shade depth% on properties of melange yarn. ANOVA analysis shows that there is significant effect of noil extraction and shade depth on all yarn properties. Fibre fineness also shows significant effect on unevenness, tensile, abrasion, yarn metal friction properties except breaking extension and hairiness. Better yarn quality with respect to yarn evenness, imperfections, hairiness, tenacity, breaking extension, yarn metal friction and yarn abrasion resistance RRI is achieved for lower shade depth melange yarn. The properties of melange yarn with higher noil extracted at comber stage are noticeably better in respect of tensile strength, elongation, hairiness, mass irregularity, imperfections and yarn abrasion resistance RRI.

In accordance with developing technologies in textile and garment industries, innovative products are submitted to the market continuously. Almost each innovative product introduced to the market provides a different functionality to the textiles such as breathability, lightweight, ultrathin etc. Some of the functional designs are turned into commercial products and some of them are still in experimental stage. In this study, it is aimed to analyze the worsted fabrics, which was designed to have higher tensile properties. Within the scope of this study, worsted fabrics produced from wool and high tenacity polyamide 6.6 fibers, which were mixed in the blend, with/without elastane. Compression, extensibility, bending rigidity, shear rigidity, tear strength, breaking strength and abrasion resistance properties of the fabrics were measured. According to the results, the use of elastane in the fabric structure causes an increase in the surface thickness, extensibility, formability of the fabrics, and a decrease in the bending rigidity, shear rigidity of the fabrics. Besides, the fabrics produced in this study have generally high tensile and abrasion resistance performance because of the high tenacity polyamide 6.6. © 2019, The Korean Fiber Society.

Textile materials produced from a high tenacity industrial polyester fiber are most widely used in the mechanical rubber goods industry to reinforce conveyor belts, tire cords, and hoses. Reinforcement of textile rubber undergoes a vulcanization process to adhere the textile materials with the rubber and to enhance the physio-mechanical properties of the product. The vulcanization process has an influence on the textile material being used as a reinforcement. In this work, the effects of aging temperature and time on the high tenacity polyester yarn’s mechanical and surface structural properties were investigated. An experiment was carried out on a pre-activated high tenacity polyester yarn of different linear densities, by aging the yarn specimens under various aging temperatures of 140, 160, 200, and 220 °C for six, twelve, and thirty-five minutes of aging time. The tensile properties and surface structural change in the yarns pre- and post-aging were studied. The investigation illustrates that aging time and temperature influence the surface structure of the fiber, tenacity, and elongation properties of the yarn. Compared to unaged yarn, an almost five times higher percentage of elongation was obtained for the samples aged at 220 °C for 6 min, while the lowest tenacity was obtained for the sample subjected to aging under 220 °C for 35 min.

We characterised fibres and papers of microfibrillated silk from Bombyx mori produced by mechanical and enzymatic process. Milling increased the specific surface area of fibres from 1.5 to 8.5 m2/g and that enzymatic pre-treatment increased it further to 16.5 m2/g. These fibrils produced a uniform, significantly strong (tenacity 55 Nm/g) and stiff (Young's modulus > 2 GPa) papers. Enzymatic pre-treatment did not reduce molecular weight and tensile strength of papers but significantly improved fibrillation. Silk remained highly crystalline throughout the fibrillation process. Protease biodegradation was more rapid after fibrillation. Biodegradation was impacted by structural change due to enzymatic pre-treatment during the fibrillation. Biodegraded silk had much higher thermal degradation temperature. The unique combination of high strength, slow yet predicable degradation and controllable wicking properties make the materials ideally suited to biomedical and healthcare applications.

Composites are gradually becoming an integral material for structural and manufacturing processes. Sisal fibre has the potential to be one of the leading reinforcement natural fibres, not only in Zimbabwe, but the world over for use in glass composites. This is mainly due to it being inexpensive, exhibiting a low density, high specific strength, a high stiffness to weight ratio, non-toxicity, its abundance in Zimbabwe and its renewability. With an aim of coming up with a composite for partition board applications in the construction industry, five samples of sisal-glass composite were prepared with varying sisal fibre content and different layering techniques. Sisal fibres were pre-treated with 20% NaOH to enhance their crosslinking with the resin and reduce the chemical impurities such as lignin and waxes. Mechanical (flexural test, hardness, and tensile strength) and physical tests (density and water absorption) were conducted to analyse the properties of the composite. The results showed that treated sisal fibres had a higher breaking tenacity of 33.11 g/tex which is higher than untreated fibres with a breaking tenacity of 25.72 g/tex. The best properties were obtained in the sample with 4 layers of glass and 9 layers of sisal fibres using 200 ml of resin. The composite had a tensile strength of 57.60 MPa, flexural strength of 36 N/mm2, moisture absorption of 10% and a burning rate of 9.82 mm/min. These results were then compared with those of the current partition boards in the market. It was noted that the composite was suitable for use in partition boards. Again, regarding cost, these composites are cheaper to produce at a rate of $11.33/m2 compared to the timber costing at $16/m2.

Manufacturing carbon nanotube (CNT) fibres on a large scale with properties that are a significant fraction of those measured for individual tubes or smaller bundles is crucial to achieving greater impact in industrial applications. We describe three macrostructured morphologies produced on a laboratory scale: CNT ribbons, ropes and tows, wherein tows are the most suitable for industrial scale-up, comprising a bundled structure of thousands of individual micro-fibres. For each morphology, we present the tensile failure mechanisms and mechanical performance observed over six orders of magnitude of strain rate. The tests were conducted on a conventional Hounsfield tensile tester (10─4 to 10─1 s─1 strain rate) and a modified split-Hopkinson tensile bar tester (30–150 s─1 strain rate). To avoid the problem of clamp failure, we present a novel method of testing loops, rather than uniaxial samples, as-produced from our chemical vapour deposition reactor. For material benchmarking and validation, we also tested unsized carbon fibre (Hexcel AS4) and Dyneema tows (SK25). All materials were used ‘dry’, i.e. not as a composite, for raw material and structure comparison. We show here that CNT tows exhibit both a mechanical performance and fracture behaviour which combines the ductility of Dyneema with the tenacity of carbon fibre.

Inter-yarn friction plays a pivotal role in determining the impact resistance of woven fabric based soft armour panels (SAPs). The current study presents a comparison of ballistic response of SAPs made from para-aramid, ultra-high molecular weight polyethylene (UHMWPE) and poly para-phenylene-2,6-benzobisoxazole (PBO) woven fabrics and demonstrates the importance of inter-yarn friction. Plain woven fabrics were prepared using para-aramid, UHMWPE and PBO yarns and SAPs of constant areal density was produced using multiple layers of these fabrics. It is found that despite lower tenacity and modulus of para-aramid fibres, in comparison to those of UHMWPE and PBO fibres, para-aramid SAP exhibits the lowest back face signature (BFS) owing to the highest inter-yarn friction. On comparing UHMWPE based SAPs made from fabrics with yarns of different fineness, fine UHMWPE yarn based fabric exhibits higher inter-yarn friction owing to more crossovers per unit length, which further translates into lower BFS of respective SAP. Therefore, while selecting fibres for soft body armour applications, inter-yarn friction should be considered along with the tensile properties.

Ensete ventricosum (EV) fibre is a lignocellulosic plant fibre hitherto, to the best of our knowledge, unexplored in terms of its response to alkali treatment at room temperature. The chemical compositions as well as physical and tensile properties of this fibre were evaluated after alkali treatment (in 2–15%w/v NaOH at 23 ± 2 °C for 1 h). Effects of alkali concentration on fibre properties were analysed and compared with that of untreated fibres. EV fibres treated with alkali solutions between 2 and 10% (w/v NaOH) exhibited all round improvement in physical, morphological, tensile, structural and thermal properties as compared to that of untreated EV fibres. Unlike the cellulose content, hemicellulose content of alkalized fibres decreased substantially with increase in alkali concentration. The 10% NaOH treated fibres showed the highest improvement in tenacity (9.1 gf/den), crystallinity index (71%) and other properties. Changes in fibre properties were further confirmed by SEM, XRD and TGA.

Based on the characteristics of high tenacity, low density, flexible design, the coated fabric has emerged as a promising construct for tensile test. Here, it reports the deformation mechanism of a PU-coated multi-axial warp-knitted fabric under uniaxial tensile via a digital image correlation system. Specimens produced by us are chase in three fibre-reinforced directions namely 0°, 45° and 90°, respectively. The result shows that the crease does not have an effect on the deformations in the small deformation range (strain

Electrospinning (e-spinning) is an emerging technique to prepare ultrafine fibers. Polyphenylene sulfide (PPS) is a high-performance resin which does not dissolve in any solvent at room temperature. Commercial PPS fibers are produced mainly by meltblown or spunbonded process to give fibers ~20 μm in diameter. In this research, an in-house designed melt electrospinning device was used to fabricate ultrafine PPS fibers, and the e-spinning operation conducted under inert gas to keep PPS fibers from oxidizing. Under the optimum e-spinning conditions (3 mm of nozzle diameter, 30 kV of electrostatic voltage, and 9.5 cm of tip-to-collector distance), the as-spun fibers were less than 8.0 μm in diameter. After characterization, the resultant PPS fibers showed uniform diameter and structural stability. Compared with commercial PPS staple fibers, the obtained fibers had a cold crystallization peak and 10 times higher storage modulus, thereby offering better tensile tenacity and more than 400% elongation at break.

Of the different techniques to produce conductive yarns for e-textiles, multicomponent hybrid yarns with continuous metallic filaments are well known for its ease in processability, better durability, and conductivity. Continuous metallic wires in yarn’s core have been researched vigorously, but since the metal wires are stiff, they produce fabrics with open interstices and make the fabric transparent towards higher-frequency electromagnetic waves. Moreover, this problem further elevates with an attempt to increase the amount of metallic content to improve the electromagnetic shielding capabilities. Continuous metallic filament, wound as spiral covers on textile core in form of hybrid cover yarns, is proven to have better control of the metallic component via altering the turns per meter of the coverings, which also improves the electromagnetic shielding capabilities of the ultimate fabrics. However, the consequence of this alternate orientation on the tensile and mechanical properties of the fabrics has never been studied. This study analyzes the mechanical properties of copper-covered polyester yarns. This orientation of hybrid cover yarns is far much superior in terms of the yarn’s tensile properties with around fourfold increase in the tenacity values and around 30–70% reduction in modulus values. The fabrics prepared from the copper-covered yarn design required around 50–200% more force at around 200% more elongation to rupture, as compared to the conventional fabric design. Moreover, the fabric stiffness and abrasion properties in the copper-covered orientation also improve, but at the cost of increased static friction of the fabrics.

The present work investigates the potential of developing bio-composites based on thermoplastic polymers reinforced with natural fibres by using hybrid yarns. The hybrid yarns were produced by the wrapping technique, in which a multifilament of polyamide 11 (PA11) was wrapped around an untreated low-twisted hemp roving to produce a yarn with sufficient tenacity and stiffness for the next step of weaving. The tensile behaviour of the wrapped yarns was identified both in the dry- and thermo-state. Then, two different fabrics were woven and tested to study the influence of yarn densities and weave diagrams on the tensile and flexural properties. At this fabric scale, properties of fabrics made from hybrid yarns were compared with those of fabrics from a previous study made from 100% hemp roving. Composites made from these fabrics, with stacking of two cross-plies, were produced by thermocompression and characterised regarding mechanical strength.

The study evaluates comparatively some physical and chemical properties of polyamide 6.6 standard and biodegradable. It also evaluates the period of biodegradation of the biodegradable yarn sample and standard sample. The physical properties analyzed were tensile strength, elongation, and tenacity. The chemical properties were related to the behavior of the samples in dyeing and the evaluation of subsequent strength dyeing. The evaluated samples were taken from knitwear produced with polyamide textured filament yarn 80 dtex f 68x1, standard and biodegradable, being purged, bleached, and dyed. The results of the physical tests, although statistically different, have values ​​very near the average, which in practice represent acceptable values ​​within the statistical control process. Both standard and biodegradable samples had the same chemical behavior and there is no difference. Concerning to biodegradation time under laboratory conditions, the carbon dioxide produced by the samples was monitored and measured to determine the percentage of biodegradation according to ASTM D 5511. After 735 days the percentage of biodegradation of the biodegradable yarn was 81.7% and of the normal yarn was 5.2%. This is an expressive gain in ecological terms for synthetic fiber.

The classification of acrylic textile wastes based on source is important, because each waste type from different sources greatly affects product quality. This study primarily deals with recycled acrylic fibers obtained from three categories of acrylic-based tops, yarn, and fabric waste through a mechanical recycling method of garneting. With the use of recycled acrylic fiber types as 100 % ratio and in blends with recycled cotton and virgin polyester fibers, open-end yarns in two twist coefficients were produced, and then the effects of these selected materials and twist coefficient on the unevenness (CVm) and tensile properties of the yarns were discussed. The 100 % recycled acrylic yarn type produced from the tops waste type revealed the lowest CVm results and the highest tenacity and breaking elongation results. The blending of the virgin polyester fiber with the recycled acrylic fiber types improved the tenacity results. It can be concluded that tops, yarn, and fabric acrylic wastes have potential to be used as sustainable and low-cost sources of raw material in the production of open yarns of acceptable quality.

Up to now, the most conventional methods for descaling of wool fibre are based on chemical degradation and resin covering of scales or a combination of them. These methods are producing wastewater and can cover physical properties of the fibres beside scales orderly. In this study, a new and clean method is developed on the basis of abrasion effect of calcium carbonate Nano particles (CCNP) in an ultrasonic bath. Woolen Samples (fibre and yarn) were sonicated with different levels of CCNP. Tensile properties of the yarns, directional friction effect of the fibres and scanning electron microscope images of the fibres were studied. Test results showed that sonicated Nano treatment of wool yarn reduced its tenacity, extension and work of rupture and increased its coefficient of friction. Scanning electron microscope images of fibres and measurement of fibres directional displacement confirmed descaling of Nano abrasive treated wool samples in comparison to the raw wool. keywords: Wool, Descaling, Nano abrasive CaCO3, Ultrasonic, tenacity, directional friction, SEM.

The objective of this work is to determine an adequate number of samples for an accurate prediction of tensile strength of fibres using a Weibull distribution. Theory will be compared to experimental results in order to know the effect of experimental errors on the theoretical expectations. The diameter and strength distribution of high tenacity viscose were evaluated. The chosen Weibull distribution was with two parameters. First, the best probability estimator for Weibull was determined using a random selection of experimental datas. Then, in order to be able to predict the number of sample knowing the variation of the Weibull modulus m, different relationship between the coefficient of variation of m and the number of sample n were tested. The relationship CV = 0.78/ $$\sqrt n$$ presented good agreement with experimental datas. The influence of the variation of m on the predicted value of strength was studied in order to determine an adequate number of sample to obtain limited variation of the predicted strength. The last part focus on experimental verification of the points previously developed. It was shown that it is possible to determine the influence of the variation of the Weibull modulus on the predicted strength. However, no correlation was found between the variations of the Weibull modulus and the error on the predicted strength.

The present research work was carried out to develop the prediction models for blended ring spun yarn evenness and tensile parameters using artificial neural networks (ANNs) and multiple linear regression (MLR). Polyester/cotton blend ratio, twist multiplier, back roller hardness and break draft ratio were used as input parameters to predict yarn evenness in terms of CVm% and yarn tensile properties in terms of tenacity and elongation. Feed forward neural networks with Bayesian regularisation support were successfully trained and tested using the available experimental data. The coefficients of determination of ANN and regression models indicate that there is a strong correlation between the measured and predicted yarn characteristics with an acceptable mean absolute error values. The comparative analysis of two modelling techniques shows that the ANNs perform better than the MLR models. The relative importance of input variables was determined using rank analysis through input saliency test on optimised ANN models and standardised coefficients of regression models. These models are suitable for yarn manufacturers and can be used within the investigated knowledge domain.

A wide variety of marine animals, including animals as different as cephalopods, echinoderms and fish, use suction adhesion for temporary or long-term attachments (1). One aspect of suction adhesion that has been discussed, but never tested experimentally, is its dependence on depth. The change in hydrostatic pressure with depth may exert a marked effect on the force of attachment produced by suction (2-6). This study was designed to confirm this effect experimentally, using limpets as a test case. Limpets rely on suction to resist dislodgment by predators and crashing waves (7, 8). We measured the suction tenacity of four species of limpets at sea level and at increased ambient pressure in a hyperbaric chamber. Tenacity is defined as the force of attachment divided by the area of the foot contacting the substratum. Change in ambient pressure had a small but significant effect on limpet tenacity. These results show that depth can affect attachment up to a point, but the mechanics of limpet feet appear incapable of producing dramatically larger tenacities. Increasing hydrostatic pressure raises the upper limit on the force of attachment that a sucker can create (5). This can be explained as follows. A sucker forms an attachment by decreasing the pressure of the water it encloses. This results in a differential between the pressure of the water outside the sucker and the pressure inside. This differential pulls the sucker against the substratum. The pressure outside the sucker is the ambient pressure, which increases by 100 kPa (1 atm) with each 0-m depth increase. The minimum pressure inside the sucker is limited by water's tensile strength. The sucker can reduce the pressure until the tension in the water reaches a critical value, at which point the water cavitates; it undergoes

Elastane containing denim fabrics which are known as “blue jeans” have always been popular. Denim fabrics are woven with white elastane-cotton weft yarns and 100% cotton indigo dyed warp yarns. The most distinctive feature of denim fabrics is those warp yarns’ indigo color fading after washing processes which enhance the denim fabrics having unique structures. The elastane amount in the weft yarns determines the flexibility ratio of the denim fabric with its high recovery property. This study aims to investigate the denim fabrics produced at three different weft and warp density with different yarn counts and elastane ratios in terms of tenacity and stretching properties (elongation, permanent elongation, elastic recovery) considering the washing cycles of 0, 5 and 15. Three different denim fabrics with 100% cotton warp yarns and cottonelastane weft yarns were produced at the weft densities of 23,19, 24 (pick/cm) and at the warp densities of 33, 28 and 35 (end/cm) with three different elastane percentages of 4%, 1% and 2.5% respectively. The 2/1 twill denim fabrics were produced on dobby weaving machine. Home laundry process was applied at 30°C for 40 minutes by using 20 ml/kg standard reference detergent containing 5%-15% anionic surface active agents

In this study, it was focused on the investigation of comfort-related properties of the fabrics treated with microcapsules containing phase change materials (PCMs microcapsules). There are limited findings about the effect of prepared PCM microcapsules on fabric properties related with the tactile comfort. In this work, we applied our produced microcapsules to the cotton fabrics and researched these fabrics’ tactile comfort-related properties such as bending rigidity, drape, fabric–fabric friction, and tenacity. One of the outstanding properties of our microcapsules is reactive carboxylic acid groups on their wall. They have the ability to bind to the fabrics in terms of their reactive chemical groups. Microcapsules on the fabrics can be durable to the effects of the rubbing and repeated washings. The fabric test results indicated that air permeability, bending rigidity, tensile strength decrease with the microcapsule treatment, whereas the fabric drape and coefficient of friction of the fabrics increase ...

Carbon nanotube (CNT) yarns were evaluated for sensor applications by measuring electrical properties during uniaxial tension loading. Mechanical properties (tenacity and failure strain) and electrical properties (resistivity and gauge factor) were investigated and statistical distributions for these properties were obtained. Cyclic loading test results showed that permanent strain after unloading exists and that the resistance at zero load increases linearly with permanent strain. Furthermore, the relative resistance change during loading was found to be linear with strain. Although mechanical properties of CNT yarns exhibited a significant statistical variation, the resistance was found to have much less statistical variation making them good candidates as sensors for structural health monitoring in composites.

In this work, the crystalline morphologies and mechanical properties of olefin multiblock copolymer (OBC) were regulated by blending with polymers possessing architecture similar to the constituent blocks. In order to understand the influence of multiblock architecture on the interaction between OBC and blended substances, ethylene-octene random copolymer (ORC) with similar crystallinity was blended with corresponding substances for comparison. We found that polyethylene (PE) chains, which possessed architecture resembling hard blocks, were inclined to cocrystallize with OBC and form remarkable lamellar structure in their blends. On the contrary, they aggregated together in ORC matrix and developed crystals similar to pure PE. The distinct crystalline properties were closely correlated to their state in the melt as revealed by Time–Temperature superposition examinations. The results of tensile tests exhibited that the strength of OBC samples could be improved without great depression of tenacity when appropriate amount of PE was blended. This might be ascribed to the good compatibility between added PE and OBC hard blocks considering their similar chain architecture. The findings contribute to understanding the relationship between morphologies and apparent properties of multi-block copolymer-based blends, which can be significant to achieve target mechanical properties for multiblock copolymers by a simply blending approach.

This study uses 0.08mm copper wire and nickel-coated copper wire as the core and 75 D far infrared filament as the wrapped material to manufacture Cu/FIR-PET wrapped yarn, Ni-Cu/FIR-PET wrapped yarn and Ni-Cu/Cu/FIR-PET wrapped yarn. The three optimum metallic/FIR-PET wrapped yarns are then weaving into Cu/FIR-PET woven fabrics, Ni-Cu/FIR-PET woven fabrics and Ni-Cu/Cu/FIR-PET woven fabrics. Tensile property of metallic/FIR-PET wrapped yarns, electrical resistance of metallic/FIR-PET wrapped yarns, surface resistivity of metallic/FIR-PET woven fabrics and electromagnetic shielding effectiveness of metallic/FIR-PET woven fabric are discussed. According to the results, the optimum tenacity and elongation are chosen as 7 turns/ cm, electrical resistance of Ni-Cu/Cu/FIR-PET wrapped presents the best value, Cu/FIR-PET woven fabric has the lowest surface resistivity and Ni-Cu/Cu/FIR-PET woven fabric shows the best EMSE at 37.61 dB when the laminating-layer number is double layer and laminating at 90 ̊. In this study, three kinds of metallic/FIR-PET woven fabrics are successfully manufactured and looking forward to applying on industrial domains.

In this study we report on the effect of feed yarn parameters viz., filament fineness, filament shape and total linear density on physical bulk, instability and strength of air-jet textured yarns. The yarns were textured under optimum process parameters. The inertial mass, surface area and directional bending effect of filaments affect the physical bulk, stability of loops and tensile strength of air-jet textured yarns. It is observed that an increase in linear density of filament results in a decrease in air-jet textured yarn physical bulk and loss in tenacity, while instability increases. Higher total yarn denier leads to higher physical bulk and instability and lower loss in tenacity. Trilobal polyester filament produces highest physical bulk and loss in tenacity; and lowest yarn instability, while rice shaped filament show lowest physical bulk. Circular filament show intermediate physical bulk and loss in tenacity and highest instability.

An ultra-lightweight engineered cementitious composite (ECC) mixture has been recently developed as a durable alternative to the conventional cement-based fireproofing material for steel structures. The newly developed mixture has a dry density of 550 kg/m3, yet as a fireproofing material, it shows considerable tensile strength above 1 MPa and tensile strain capacity greater than 2%. This newly developed mixture is much more lightweight than any previously developed ECC material. It uses high tenacity polypropylene (HTPP) fibers as fiber reinforcement; and an acrylic latex based admixture is incorporated into the mix composition. All these leads to significantly different micromechanical properties from all previously developed normal-weight and lightweight ECC mixtures. In this paper, investigations have been conducted to fully understand the unique micromechanics of the newly developed material. Specifically, single fiber pull-out tests were conducted. The test result showed that a cement-polymer co-matrix was formed in presence of the latex admixture. As a result, the interfacial bond between the lightweight matrix and HTPP fibers was significantly enhanced. A scale-linking model was also used to show that such enhanced interfacial bond contributed to an increase of tensile strength and strain-hardening potential. The current research provides useful data for understanding the behavior of lightweight ECC and polymer modified ECC materials and can also serve as a guideline for future development of similar materials.

Usage of unexplored lesser known natural fibres in the global arena is not only the important striking area, but simultaneously to search out a suitable avenue for which separate spinning system is not widely available or established. Blending of different fibres having similar or different properties is an important consideration to upgrade certain functional properties of textiles either in apparel or in technical textiles. The theory based on the mechanical properties of the component fibres of blended yarn is well explained by Hamburger in 1949. Blending of indigenous ramie with jute/acrylic will help development of textiles with better functional properties by combining positive features of both the fibres. The tensile properties of blended yarns and influence of component fibres on mechanical characteristics of indigenous ramie-jute and ramie-acrylic blends spun on existing jute spinning frame with an appropriate processing technology divulges that fibre properties like tenacity, fineness and breaking extension mainly dominates the tensile characteristics of the blended yarn.

Four hyperbranched polysiloxanes (HPSis) with different molecular weights and concentration ratios of double bonds to epoxy groups (1:6.5–1:0.7) were synthesized and characterized. Each HPSi was facilely grafted onto surfaces of Kevlar fibers (KFs) to develop novel modified fibers (HPSi-g-KFs). The structures and integrated properties of HPSi-g-KFs as well as the origin behind were systematically investigated. Results show that HPSi-g-KFs have much rougher surface morphologies, and their surface free energies are as high as about 1.7 times that of KFs, showing greatly improved wettability. Besides, HPSi-g-KFs have excellent UV resistance after 168 h UV irradiation, the retentions of tenacity, energy to break, modulus and break extension are as high as 92, 86, 95 and 96%, respectively, while those of KFs are 66–85%. In addition, compared with KFs, HPSi-g-KFs have higher tensile tenacity and energy to break with similar modulus and break extension, much better thermal stability and flame retardancy. The nature of HPSi has different influence on different property of fibers, the HPSi with smaller molecular weight and more epoxy groups is beneficial to prepare HPSi-g-KFs with better wettability, while that with larger molecular weight and more double bonds tends to prepare HPSi-g-KF with better flame retardancy and UV resistance.

The effect of fiber cement interactions and its influence on flexural and tensile properties of cementitious composites are well known. In this research, acrylic fibers with different cross sectional and longitudinal shapes and different tensile strengths were selected as reinforcement of the specific fine aggregates concrete. Three point bending test, pullout test, and scanning electron microscopy were used to investigate flexural and pullout behavior of the composites. It was found that flexural toughness and pullout strength were increased 20% and 34%, respectively, by application of kidney shaped acrylic fibers in comparison to dog bone shaped acrylic fibers. It was also found that the flexural and pullout strength of composites containing non-crimped fibers are 33% and 26.5% higher than specimens with crimped fibers, respectively. Results showed that the flexural toughness and pullout strength of high tenacity fiber is 75% and 131% higher than regular fiber as well, respectively. The effect of fine aggregates on the adhesion of fibers to cement matrix was evaluated.

A range of polyacrylonitrile (PAN) and pitch based carbon fibre types (high, standard and intermediate modulus fibres) have been characterised using both physical and chemical techniques, the results highlighting the heterogeneity of the fibre. Nano-indentation showed variation in stiffness between different fibres of the same type as well as variation along a 20 μm length of a single fibre. Tensile tests showed variance of approximately 25% in tenacity for three different carbon fibre types but less variability in modulus with values from 8% to 19%. Raman spectroscopy showed variation in the graphitic content both between fibres of different origin as well as variation, with 0.5 μm spatial resolution, along the length of a single fibre. Inverse gas chromatography surface energy measurements of larger samples of fibres were carried out using the novel approach of incremental surface coverage by varying the probe molecule concentration and revealed different levels of energetic heterogeneity for PAN based fibres collected at different stages of carbon fibre production. The heterogeneity of the unoxidised fibres (collected after carbonisation) was restricted to about 15% of the fibre surface whereas the surface oxidised fibre sample (collected after the electrolytic oxidation bath) was heterogeneous over more than 30% and the sized fibres were shown to be quite homogeneous.

6 pages; International audience; The production of natural fibers is not sufficient to accommodate the textile needs of the growing world population. Therefore, textile research is exploring alternative natural resources to produce fibers. Though typically known for its nutritional use, the sugarcane can also be used for textile production because of its high fiber content.The aim of our study was to extract fibers from sugarcane and to analyze their mechanical behavior. Cane particles were treated with an alkaline solution in order to get cellulosic fibers. Physical and mechanical characterizations were carried out on these fibers: linear density, fineness, tensile properties, and bending rigidity. Their microstructure was analyzed to better understand their behavior. The results showed a strong influence of extraction parameters on the characteristics of fibers. Depending on these parameters, fibers fineness ranged from 8 to 80 tex, length ranged from 19 to 62 mm, and tenacity ranged from 7 and 25 cN/tex.

In order to understand the mechanical properties of the soybean protein fibers (simply called SPF) in different processing condition, the tensile and frictional properties of the SPF are measured with different instruments. By the analysis of the results, the following conclusions can be deduced: bleaching has an influence on decreasing tenacity at break for each test modality. Knotted and looped modalities decrease fiber tenacity remarkably in all three samples, and the same occurs with elongation at break. Looped modalities show lower tenacity and elongation at break, the lowest being the bleached fibers in looped modalities.

This paper presents a study of hybrid effect on mechanical properties of tencel blended ring-, rotor- and Murata jet spinning yarns. The tensile strength, breaking elongation, flexural rigidity and abrasion resistance of tencel-polyester and tencel-cotton blended yarns are examined and compared with the value predicted using linear and quadratic rule of mixture (ROM). It is observed that there is no significant hybrid effect on abrasion resistance of tencel-polyester mix yarns and tenacity and breaking extension of tencel-cotton mix yarns; hence, a linear ROM is found better in predicting the yarn properties. Further, for all yarn types, there is a significant hybrid effect on tenacity, breaking extension and flexural rigidity of tencel-polyester mixes and flexural rigidity and abrasion resistance of tencel-cotton mixes. A quadratic ROM model suits well for these yarns. Overall, it is found that there is a negative hybrid effect on tenacity and breaking extension whereas there is a positive hybrid effect ...

Eco-friendly and health-functional clothing is now becoming the target of the worldwide hot trends. The purpose of this study is to develop an eco-friendly textiles to decrease environmental pollution and to be harmless for human health by investigating how the natural chorangak liquid treatment affects the changes of mechanical properties and the hand of silk fabrics according to different treatment conditions. Treatment was varied with various temperatures (, , ) for 90 seconds after degumming. The results were as follows: 1) The natural chorangak liquid is the most effective at the ratio of glacial acid 200ml with eggshell 20g minimizing the time limit and sludge reduction. Its treatment of silk fabrics is optimized at for 90 seconds with 25% conc. after degumming when considering tenacity and elongation. 2) After the treatment, tenacity and elongation of specimen are increased compared with those of degummed silk fabrics. 3) After analyzing the effect of the treatment on the characteristic values of basic mechanical properties of silk fabrics, mechanical properties (tensile, bending, shearing, compression, surface) are overall improved. The properties of thickness and weight are increased as well. 4) Based on the clear analysis on effects of the treatment on the mechanical properties and the hand of silk fabrics, the level of THV was enhanced from good to excellent. Therefore, chorangak liquid can be utilized satisfactorily as a new finishing agent for developing eco-friendly textiles.

The linear density of the raw and degummed plant fibers such as ginger (zingiber officinale), turmeric (curcuma longa) and java galangal (alpinia galangal) fibers has been determined by the use of a Vibromat M. The stress-elongation curves for the fibers were drawn by using a Tensile Tester with electric strain gauges 'Fefegraph' for each of the specimen fiber; at temperature 250 C and 65% R.H. Various tensile parameters have been calculated from the stress-elongation curve obtained by using the Tensile tester with electric strain gauges 'Fefegraph'; and the linear density by a 'Vibromat M'. It is observed that the tenacity is linearly related with the linear density. From various investigations it has been concluded that all the plant fibers in present investigation are hygroscopic in nature and the hygroscopicity does not change due to irradiation and degumming.

Utilization of underexploited natural fibres are not only the major thrust area in the international scenario but also the need of the hour. Blending of different fibres having similar or different properties is an important issue globally in the area of textiles. Blending of indigenous ramie with acrylic will help development of textiles with better functional properties by combining positive features of both the fibres. The mechanical properties of blended yarns and performance of indigenous ramie-acrylic blends on conventional jute spinning frame reveals that properties of fibre like tenacity, fineness and breaking extension mainly governs the tensile characteristics of the blended yarn. The critical blend level for 4 denier acrylic fibre and indigenous ramie has been found to be 62/38. The theoretical and actual blend composition by chemical method reveals matching with each other.

This study evaluates the specific stress (tenacity) and strain (elongation) of polyamide 6 staple fibers, which were virgin, punch-needled on the press felt, and worn on the press felt under simulated wet-pressing conditions. The staple fibers were distinguished by molecular weights. The fiber deformation and defects were microscopically characterized after the felt preparation and aging. We discovered that the tensile breaking force and elongation of the polyamide 6 staple fibers decreased markedly during the felt preparation and aging. The mechanical reduction of staple fibers reflected their tenacity, work, and modulus values. Surprisingly, the linear density of staple fibers remained unchanged – although fibers strongly deformed and lost their mechanical properties after the felt aging. The results indicate that an increase in molecular weight improves the mechanical durability of staple fibers, the preparation of the press felt (punch-needling) decreases the tenacity and elongation of staple fibers, and humidity provokes their degradation.

This paper has studied the structure and property of high tenacity polyamide 6 upon different draw ratios and heat styling temperature process conditions, characterized with wide-angle X-ray diffraction (WAXD), sound velocity method, Fourier transform infrared (FTIR) spectroscopy, amino-terminated content determination and essential property texts such as the absorption of moisture and dyeing. It was demonstrated that increasing the draw ratio (DR) and heat styling temperature were conducive to crystal-to-crystal transformation and stabilizing the internal structure of fibers. The temperature played a significant role in orientation of high tenacity polyamide 6, particularly subjected to a higher heat styling temperature, owing to its thermo plasticity. And increasing the draw ratio and heat styling temperature were both conducive to the tensile property, but little beneficial impact on moisture property. The high tenacity polyamide 6 exert a good effect on absorption of moisture and acid dye, and for dyeing the effects of hydrogen-bond as well as the van der Waals’ force play a significant role in dye pickup, especially in the high tenacity polyamide 6 upon different draw ratios.

In order to study the tensile mechanical properties of the double protein modified fiber. Tensile breaking property and stress relaxation were analyzed and proper mechanical models were selected for fitting. The analysis shows that: in dry and wet, the straight tensile breaking tenacity of the double protein modified fiber is weaker than that of the modified soybean protein fiber, the elongation at break and initial modulus are near to those of the modified soybean protein fiber, the breaking tenacity of the double protein modified fiber increases slightly when wet while the elongation at break and initial modulus decline a little. In knotted and looped, the double protein modified fiber’s tensile breaking tenacity is weaker than that of the modified soybean protein and its tensile breaking strength and elongation at break decrease differently. The fitting reveals that the four element nonlinear viscoelastic model is the best to describe straight tensile. The two optimal models for knotted and looped tensile are the four element nonlinear viscoelastic model and the Improved Zurek model. In addition, the six element viscoelastic plasticity model is appropriate to simulate stress relaxation.

Polylactic acid (PLA) fiber, as a biodegradable synthetic aliphatic polyester fiber, has properties of biocompatibility, biodegradability and processing. Therefore, this study used PLA multifilament to prepare numerous plied yarns, respectively 75D, 75D×2, 75D×3, 75D×4 and 75D×5. Afterwards, these yarns were twisted with 3, 5, 7 twist/inch and then heat-treated respectively. The resulting yarns were tested for their tensile property tensile tenacity and tensile elongation. Moreover, the heat-treated effect was discussed on influencing tensile property.

The protein structures of wool, treated in fabric form with ultrasonics for different time durations, were analysed by X-ray diffraction (XRD) and Fourier transform infrared (FTIR), in comparison with the wool without ultrasonic treatment. Fabric water absorption and tensile properties were measured in addition to the fibre micro-structure analysis. It is shown that while the ultrasonic treatment had little effect on the fibre crystallinity, some chemical structures in the protein were altered to some extent during the process. Disruption of fibre internal waxy lipids upon ultrasonic treatment provided the fibres with increased water absorption. Protein chains in the macro fibrils were shown to be rearranged to a more regular and less flexible structure, as a result of the ultrasonic treatment. Fabric tensile tests showed an increased tenacity and a reduced extensibility to the ultrasonically treated fabric. Prolonged ultrasonic treatment, however, significantly reduced both fabric tenacity and extensibility.

The mechanical behavior of four carbon nanotube (CNT) wires, comprised of 1-yarn, 30-yarn, 60-yarn, and 100-yarn, was investigated under constant tension at two loading rates of 0.02 mm/s and 2 mm/s. Tests were conducted with both as-fabricated and pre-stressed wires. The ultimate tenacity or apparent ultimate tensile strength of all four wires was found to be independent of loading rate, with those for the single-yarn wire about twice those of the multiple-yarn wires. Strain at a given stress level and failure strain of the multiple-yarn wires before pre-stressing were almost an order of magnitude larger than those for the single-yarn wire, and this difference was reduced considerably after pre-stressing. The failure mechanisms of 1-yarn wire or twisted individual yarns in multiple-strand wires involved ductile (necking) deformation and fibrillar breakage. Inner yarns in multiple-yarn wires initially failed at the same location, followed by outer yarns failing at different locations. Additionally, sliding occurred between individual yarns, and twisting of the yarns accompanied by surface wear took place in the multiple-yarn wires, which contributed to their failure at a lower load compared to the single-yarn wire.

This study systematically investigated the drawing and ultimate tenacity properties of the Nylon 6 (NY6)/nylon 6 clay (NYC) composite fiber specimens prepared at varying NYC contents and drawing temperatures. The achievable draw ratio (Dra) values of NY6x(NYC)y as-spun fiber specimens initially increase in conjunction with NYC content, and then approach a maximum value, as their NYC contents and drawing temperature approach the 0.5 wt% and 120°C, respectively. The percentage crystallinity (Xc) values of NY6x(NYC)y as-spun fiber specimens increased significantly, as their NYC contents increased from 0 to 2 wt%. As revealed by high power wide angle X-ray diffraction analysis, α form NY6 crystals grew at the expense of γ form NY6 crystals originally present in NY6x(NYC)y as-spun fiber specimens as their draw ratios increased. The ultimate modulus, tenacity, and orientation factor values of NY6x(NYC)y fiber specimens approach a maximum value, as their NYC contents and drawing temperatures approach the 0.5 wt% and 120°C optimum values, respectively. The thermal and melt shear viscosity experiments were performed on NY6x(NYC)y resins and/or fiber specimens to determine the optimum NYC content and possible deformation mechanisms accounting for the interesting drawing, orientation, and ultimate tenacity properties found above. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers

This study reports on the analysis of tenacity and breaking elongation of ring-, rotor- and air-jet-polyester/viscose spun yarns measured using static- and dynamic tensile testers. The weavability, a measure of performance of these yarns in post spinning operations is quantified. The yarn diameters and helix angles of fibres in these yarns are measured in order to analyze the effect of types of spun yarn and blend proportion on yarn elongations. The dynamic tenacity is highly correlated with the weavability than the average static tenacity measured at 500 mm gauge length. The minimum static tenacity obtained from 100 tests has high correlation with the dynamic tenacity. The present study indicates that it is appropriate to evaluate the performance of spun yarns in winding, warping and weaving based on the dynamic yarn tenacity measured while running a 200 m length of yarn in a constant tension transport tester or the minimum static yarn tenacity obtained using any conventional constant rate extension (CRE) tensile testers corresponding to a total test length of 50 m.