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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.

Agave fibers were extracted mechanically without the use of solvents or water, through a lyophilization-assisted method. Then, the internal arrangement of the fibrils was studied in order to elaborate a hierarchical growing model, using this information to explain the outstanding properties of these natural fibers. We found that the lyophilized fibers have an initial modulus of 36.7 g/den, a breaking tenacity of 1.45 g/den and an elongation of 17 %, while the fibers washed with water after extraction presented a similar value of initial modulus (31.1 g/den), but the breaking tenacity (2.59 g/den), and the elongation (34 %) increased nearly two times, showing the embrittling effect of the freeze-drying on the fibers behavior.

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.

This paper investigated the performance and morphology of ramie fibers degummed using Fenton reagent. In order to deeply understand the reaction characteristics, SEM, XRD and FT-IR were employed to characterize the morphologies, chemical components and crystallinity of degummed fibers. Also, the physical and mechanical properties such as tenacity, breaking elongation, density, softness and degree of polymerization of degummed fibers were measured. The experimental results indicated that Fenton can serve as an effective oxidation degumming agent under weak acid condition. The new degumming method could remove more gummy components from raw ramie, whereas the cellulose content in treated fibers was further increased compared with the alkaline oxidation degumming. The fibers degummed using Fenton showed slight increase in tenacity and significant increase in density as well as breaking elongation comparing with alkaline oxidation degumming. The degummed fibers were also characterized in terms of SEM, XRD and FTIR which confirmed the effectiveness of the new degumming method.

The purpose of this study is to suggest basic data on product-development-directivity by observing how sense of vision, olfaction, and tactile applied to fabric is expressed compositively and by assessing preference of applied fabric. And the research was done by examining factor-structure of consumer’s compound sensibility on color, odor, and touch of fabrics dyed with methanol extract of Juniperus Chinensis Heartwood which not only possesses color but also functionality and odor at the same time. Evaluation on compound sensibility and preference using 20 sets of 7-point-scale was done by taking 130 men and women aging 20 s to 50 s as a research subject. Structure of compound sensibility on color, odor, and touch was drawn with 5 factors of activeness, revelation, tenacity, mildness, and naturalness. Sensibility according to type of fabrics showed significant difference on activeness, revelation, tenacity and mildness, and sensibility according to gender showed significant difference on activeness and naturalness. And according to age, meaningful difference was shown on activeness, revelation, and tenacity. Preference and purchase intention were highest in silk and ramie fabric, and fabric that most matches color and odor was ramie.

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.

Surfaces of raw wool fibers possess high amounts of greasy substances that need to be removed prior to further processing. Acidic lipases using Bacillus licheniformis (MTCC 2618) were produced with the optimum activity levels closer to the room temperature. Scouring of wool fibers using mesophile acidic lipase has been attempted, in the present work, as an alternative to the existing alkaline treatment and the samples were assessed in terms of weight loss, moisture regain, tenacity, elongation, surface appearance, and friction of the fibers. The lipase scoured wool fibers showed moisture regain and weight loss values comparable to that of alkaline treatment, with lower static and dynamic frictional coefficients. Higher tenacity and elongation values were observed in the lipase scoured fibers compared to the alkaline scoured samples and clear appearance of the surface, compared to the raw wool fibers, was also observed in the lipase scoured samples.

Sisal fibres were subjected to a 2 % sodium hydroxide solution treatment for 2, 5 and 8 h at 35 °C. Change in chemical composition of the alkali treated fibres in comparison to that of the untreated fibres was evaluated. Fibres were characterized with respect to its FTIR, linear density, crystallinity, tenacity, modulus and % breaking strain. Tenacity of the fibres increased initially and then decreased as the time of alkali treatment was increased. Modulus of elasticity of the fibres increased with increase in alkali treatment time. Fibres lost breaking strain (%) gradually with increase in treatment time. Variation in mechanical properties of composites was studied with respect to the duration time of alkali treatment of fibres. The failure mode was particularly investigated before and after treatment for better understanding of the effect of alkali treatment.

An investigation was made of the effect of basic spinning process parameters on the structure and properties of butyric-acetate copolymer of chitin (BOC) fibres. It was found that, considering the resulting tenacity of 20.3 cN/tex simultaneously with high water sorption and retention properties, it is favourable for the BOC fibre spinning process to be carried out with 1 % HAp or TCP nanoadditive. Furthermore, when 3 % of the HAp or TCP nanoadditive is incorporated into the BOC fibre material, no significant changes in the crystal structure occur compared with fibres without the nanoadditives, formed in similar conditions. Analysis of the porous structure and the properties of the surface of BOC fibres with HAp or TCP nanoadditive shows that the parameters are favourable for their medical application.

Delamination is the most common failure mode in laminated composites, due to the reduced strength in the through-the-thickness direction. This paper describes the development of core-and-effect textured glass yarns for improving the bonding strength of laminated glass woven fabric composites. Air-jet texturing introduces bulk and loops in the yarn which provides more contact surface between the fibers and the resin. However, the yarn tenacity decreases after texturing because of the reduced alignment of the filaments. The effects of texturing air pressure, yarn overfeed ratio, yarn linear density and core-sheath ratio were studied in this paper. The tenacity of glass yarns decreased significantly after the texturing process. The reduction was smaller for yarns with a higher core linear density. The effects of texturing air pressure on the tenacity were found to be insignificant.

There are various structural parameters (number of filament, cross-sectional shape, linear density, etc.) determined during the production of synthetic fibre and these parameters influence product features. Among these parameters, cross-sectional shape of fibres has a significant importance. Desired features can be added to the products by varying the cross-sectional shape and in this way; new products with improved features or with high added value can be produced. As a consequence, studies on this subject have increased recently. In this study, the effects of different cross-sectional shapes and yarn linear density on the features of polyester partially oriented yarn (POY) have been investigated. Five different cross-sectional shapes named round, trilobal, tetra, hexsa and octolobal and two different linear densities have been used in the study. Tenacity-elongation and unevenness tests have been applied onto yarns. As a result of the study, it was seen that round, tetra and octolobal cross-sectional shapes lead to production of yarn with high tenacity and breaking elongation while trilobal and hexsa leads to production of yarn with low tenacity. In addition, due to its deep-channelled structure, hexsa crosssectional shape led to POY yarn structure with a high unevenness rate. It was also seen that an increase in the rate of linear density decreased the tenacity and breaking elongation rates of yarn and reduced POY unevenness. © 2013 The Korean Fiber Society and Springer Science+Business Media Dordrecht.

The effect of spinning parameters on core-spun yarns properties manufactured using three-strand modified method (TSMM) was analyzed. Of the various spinning parameters, strand spacing, yarn linear density and yarn twist have a crucial effect on core-spun yarn properties. To achieve the objectives of this research, general physical properties of core-spun yarns together with existing standards were thoroughly studied. First of all, the strand spacing and yarn linear density were optimized. Afterwards, the effects of variation of yarn twist and sheath roving linear density on core-spun yarns properties were investigated. Finally, the physical and mechanical properties of TSMM yarns were compared with those of siro and conventional ring core-spun yarns counterparts. It was found that, the best strand spacing and yarn linear density to produce core-spun yarns are 8 mm and 45 tex, respectively. Results showed that, tenacity of TSMM yarns increases up to a certain twist level beyond which it reduces. The result confirmed that 45 tex yarns produced by three rovings of the same count are superior with regards to tenacity and hairiness. The optimized yarns produced by three-strand modified method enjoy superior physical and mechanical properties in comparison to the ring and siro core-spun yarns.

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.

Natural bamboo fibers have excellent properties suggesting that there is a good potential for them to be used in textiles; however, they have not received the attention that they deserve owing to their coarse and stiff quality. Therefore, a chemical method for extraction and modification of natural bamboo fibers for textile end uses were developed and optimized in this paper. The quality of natural bamboo fibers were characterized by their chemical composition, linear density, and tenacity. Experimental results show that the modified bamboo fibers are finer, with significant lower content of noncellulosic substances. The processing parameters are optimized as: 20 g/l NaOH, 3 g/l Na5P3O10, 5 g/l Na2SO3, 3 g/l penetrating agent, with a fiber to liquid ratio of 1:10, at 100 °C for 2 h, and the bamboo fiber thus produced has cellulose amount of 73.25 %, fineness of 3.26 tex, average length of 44.5 mm, breaking elongation of 2.8 % and tenacity of 2.41 cN/dtex. The result of this study may offer a possibility of developing natural bamboo fibers into practical applications in textiles.

The tensile properties of spun yarns decisively influence its performance in various mechanical processing stages. This study is primarily aimed at simultaneous analysis of two tensile properties of spun yarns namely tenacity and breaking strain, which play crucial role in determining the frequency of warping breaks. The threshold values of yarn tenacity and breaking strain required for 20’s Ne carded cotton yarn to sustain the imposed stresses and strains during warping process have been determined using a bivariate normal distribution model. This study opens up the possibility of minimizing end breakage rate in various manufacturing processes of textile industry by engineering of spun yarns devoid of potential weak spots which are responsible for breaks.

Core spun yarns are applied for various purposes that especially require the multi-functional performance. This research reports on the core spinning effect on the yarn strength. We prepared various core yarns by combining different kinds of high tenacity filaments in core with cotton staples in sheath with various twist levels in the ring spin system. And the tensile strength was tested to investigate the contribution of the core-sheath structure to the core yarn strength. The influence of the twist level was also checked up on the relationship between the core-sheath structure and the yarn strength. Results turned out that the core-sheath weight ratio had influence on the tensile properties of the ring core-spun yarns in different ways according to the core filaments used for the yarn. Increasing the twists yielded a monotone decreasing strength for the aramid and the basalt core yarns, while the PET core yarns showed almost unchanged strength, which could be ascribed to the extensional property of the filaments.

Although high performance fibers possess higher thermal resistant properties, they show very low sunlight stability. In this paper, a new sol-gel treatment method was used to enhance their light-resistant properties. Their mechanical property retention ratios (tenacity, extension, modulus) of fibers treated with titanium hydrosol were higher than those of the original Kevlar®129, PBO, and Kermel® fibers after light irradiation. Moreover, Kermel® fiber showed the highest improvement among the three kinds of fibers.

The present work relates to the occurrence of fibre rupture during fibre separation in rotor spinning and also discusses the mechanism of such rupture. The reduction in fibre length during opening has been studied at different span lengths. A correlation has been drawn showing the influence of combing roller action on yarn tenacity and elongation. Fibre rupture has direct relationship with opening roller speed. Fibre rupture and surface damage occurring due to action of opening roller together are found to mar the yarn quality index.

In present work, PET FDY has been used to blend with diacetate filaments by air texturing process and core-and-effect air-textured yarns have been produced. The influences of both over-feeds of core and effect components on properties of textured yarns were mainly examined. It was observed that a spun-like effect of diacetate filaments occurred during air texturing and there were a little amount of free fiber ends besides loops on blended air textured yarns, while the number of free fiber ends changed little with variation in over-feeds. The tenacity of textured yarns decreased with increase in over-feeds of effect or core component. The breaking elongation increased with increase in over-feed of effect component, but decreased with increase in over-feed of core component. The yarn stability improves when both over-feeds are increased. The effect of over-feeds on boiling water shrinkage shows no clear trend. The core and average diameters are higher at high over-feed of effect component, but the over-feed of core component exhibits little effect on yarn diameters. The number and size of loops are increase with increased over-feed of effect component.

In this article, an attempt has been made to explain the failure mechanism of spun yarns. The mechanism includes the aspects of generation and distribution of forces on a fibre under the tensile loading of a yarn, the free body diagram of forces, the conditions for gripping and slipping of a fibre, and the initiation, propagation, and ultimate yarn rupture in its weakest link. A simple mathematical model for the tenacity of spun yarns has been proposed. The model is based on the translation of fibre bundle tenacity into the yarn tenacity.

The present paper is concerned with the influence of opening roller speed, drum speed difference and suction air pressure on properties of polyester and acrylic open-end friction spun yarns. The results shows that the opening roller speed and the suction air pressure have considerable influence on the characteristics of polyester and acrylic open-end friction spun yarns. In case of polyester yarns the unevenness, imperfection and hairiness decreases and the yarn tenacity increases with the increase in opening roller speed and suction air pressure. However for acrylic yarns the unevenness and imperfections decreases and tenacity increases with the increase in opening roller speed and suction air pressure.