Yarn Strength Research Articles

Evaluation of Processing Performance and Properties of 100% Cotton and Cotton-Polyester Blended Ring Yarns

The paper provides comparison of properties of 100% cotton yarn with those of two cotton-polyester blended yarns of 50/50 and 20/80 blend ratios. In this regard three types of yarns (i.e. 100% cotton, 50/50 and 20/80 cottonpolyester blends) were produced in the ring frame and for each type two different counts (30 Ne and 40 Ne) were produced. The blending was carried out in the draw frame. During processing, the settings and parameters e.g. spindle speed and twist multiplier were adjusted for optimum performance. After production at each stage (i.e. D/F, Simplex and Ring) samples of draw frame slivers, rovings and yarns were collected and investigated. The properties that were investigated were count, yarn faults, yarn irregularity as U% and strength as CSP. The study shows that, in ring frame it was possible to maintain higher spindle speed and lower twist multiplier for 50/50 and 20/80 blended yarns than 100% cotton yarn. Between 50/50 and 20/80 blended yarns, it possible to maintain higher spindle speed and lower twist multiplier for 20/80 blend than 50/50 bend. It was observed in all cases that as the percentage of polyester increase the U% i.e. the irregularity in the sliver/yarn decreases. It was also observed that yarn faults (IPI) decreased with the increase of % of polyester in the yarns. The yarn strength of 50/50 and 20/80 blended yarns was higher than that of 100% cotton and strength of 20/80 was higher than that 50/50 blended yarn.

Modification of Rabbit Yarn by Milk Protein Grafting and Cross-Linking

Rabbit yarn was treated by milk protein grafting and cross-linking to improve its abrasion resistance performance and breaking strength. Grafting ratio and washing fastness of the rabbit yarn after graft modification were tested. The surface morphology of the rabbit yarn before and after graft modification was observed by a scanning electron microscope(SEM). The mechanical properties and friction performances of the treated and untreated rabbit yarns were also tested. The treated yarns were utilized to design and weave rabbit hair-knitted fabric. The anti-pilling resistance of the rabbit hair-knitted fabric was tested by circular locus method; the pills were then counted and weighed. The stiffness of the fabric was observed. Results showed that milk protein could obviously be grafted on the fiber surface, resulting in a rougher surface of the treated fabric than that of the untreated ones. The average grafting ratio is 3.701%. The protein retention ratio of the rabbit yarn treated by milk protein grafting and cross-linking is 99.312%. The breaking strength of the rabbit yarn was enhanced and friction performance improved significantly after treatment. The pilling grade of the fabric significantly improved and the stiffness of the fabric was reduced.

Development of new hybrid yarn construction from recycled carbon fibers for high performance composites. Part-I: basic processing of hybrid carbon fiber/polyamide 6 yarn spinning from virgin carbon fiber staple fibers

The availability of a considerable amount of waste carbon fiber (CF) and the increased pressure to recycle/reuse materials at the end of their life cycle have put the utilization of recycled CF (rCF) under the spotlight. This article reports the successful manufacturing of hybrid yarns consisting of staple CF cut from virgin CF filament yarn and polyamide 6 fibers of defined lengths (40 and 60 mm). Carding and drawing are performed to prepare slivers with improved fiber orientation and mixing for the manufacturing of hybrid yarns. The slivers are then spun into hybrid yarns on a flyer machine. The investigations reveal the influence of fiber length and mixing ratio on the quality of the card web, slivers and on the strength of the hybrid yarns. The findings based on the results of this research work will help realize value-added products from rCF on an industrial scale in the near future.

Multiscale modeling of randomly interwoven fibers for prediction of KM2 Kevlar yarn strength and damage

Modeling Kevlar yarn response as a function of twist requires creating a model at the filament level that incorporates capturing the mechanical interaction of numerous fibers. The inherent complexity of building a multiscale interwoven fibrous structure manually is prohibitive for such an endeavor; therefore, computer-aided simulations are preferred. In this study, a random walk methodology was employed to generate a fibrous structure along the axis of a yarn. Since the directionality of the fibers is randomly oriented along the axis, the fibers can wind around each other and tangle or terminate on demand. The resultant geometry can represent the tortuous path that yarn filaments experience. Yarn twist can be introduced through imposing a rotation matrix to the geometry or conducting an initial analysis that applies the preload. The analysis method employed in this paper captures the correct prestress of the twisted yarns at zero, three, and ten twists per inch. The analysis then loaded the yarn until filament fracture occurred. The predicted ultimate load was within 5% for all three twists per inch analyzed. The zero twists per inch linear response matched test results to within 5%.

A study on activated carbon nanofibrous adsorbents prepared by technology for electrospun composite yarn

In this study, an electrospinning process was used to fabricate nanofibrous PAN composite yarn. During the process, PAN spun yarn was used as the core of the composite yarn to increase the tensile strength of the nanofibrous yarn, PAN nanofibers were spun and coated onto the core surface to form a sheath of the composite yarn, so that it could be smoothly knitted and so that oxidation and carbonization/activation processes could be performed. Fabric knitted from the yarn was used as precursor for a activated carbon nanofibrous adsorbent. It was subjected to continuous heat treatment to carry out oxidation and carbonization/activation processes to examine the characteristics of the oxidized knitted fabric and of the adsorbents. The results suggest that the fiber diameter and the tensile strength of the yarn decreased after the oxidation and carbonization/activation processes. The limited-oxygen index of the oxidized fabric reached >40, indicating that it had become non-combustible. The tensile strength of the oxidized knitted fabric decreased by about 71 % relative to that of the unoxidized knitted fabric. During the carbonization/activation process, the yield of the activated carbon nanofibrous adsorbent was ∼17 %, and the ∼90 % decrease in tensile strength did not affect the processing. The BET specific surface area of the adsorbent reached ∼1100 m2/g, and the diameters of the activated carbon nanofibers were about 100–150 nm.

Improving the tensile strength of carbon nanotube yarn via one-step double [2+1] cycloadditions

The tensile strength of a CNT yarn was improved through simple one-step double [2+1] cycloaddition reactions that crosslinked the constituent CNTs using a polyethylene glycol (PEG)-diazide crosslinker. The FT-IR spectrum confirmed that the azide groups in the PEG-diazide were converted into aziridine rings, indicating that the cycloaddition reaction was successful. The generation of crosslinked CNTs was also supported by the observation of N1s peak in the XPS spectrum and the increased thermal stability of the material, as observed by TGA. The tensile strength of the CNT yarn was increased from 0.2GPa to 1.4GPa after the crosslinking reaction when twisted at 4000 twists/ meter. The appropriate selection of the crosslinker may further optimize the CNT yarn crosslinking reaction. The simplicity of this one-step crosslinking reaction provides an economical approach to the mass production of high-strength CNT yarns.

Theoretical analysis on the yarn twist mechanism of self-twist jet vortex spinning

In this paper, the hollow spindle receives self-twist modifying treatment, which makes the surface friction coefficient of the hollow spindle increase. When the sliding friction torque is enough to overcome the torsional stiffness of the fiber, under the force of the high-speed airflow, the fiber scrolls on the surface of hollow spindle, resulting in fiber twist, which increases the cohesion between the fibers, improving yarn strength. Based on the flow field simulation of the self-twist jet vortex spinning, it establishes the mechanical system of the free-end self-twist motion of the fiber in the flow field, and analyzes the fracture mechanism of the self-twist jet vortex spinning yarn. It provides more comprehensive support for the design and processing of the key components of the self-twist jet vortex spinning system.

Effect of Wrinkle Free Finishing of Cotton Twill Fabric

Wrinkle free finishing is a widely used functional finishing process to produce wrinkle-resistant cotton fabrics at the expense of tearing strength of fabrics. In this research, full factors and orthogonal experiments were carried out to invesitgate the mechnism between the wrinkle recovery and tearing strength of cotton fabrics. Wrinkle recovery angle (WRA) was tested by AATCC Test Method 66–2003. Fabric tearing strength, interwoven resistance, and yarn strength were tested before and after resin treatment by a tensile testing machine. By full factors experiment, it was found that the specimen could achieve its best wrinkle-free performance at 110°C curing temperature, 2.5 minutes curing time, 80% pick-up percentage and 60g/l resin concentration considering fabric tearing strength. It is found out that after resin treatment in optimum condition, it could effectively improve the WRA and at the same time with the minimum lose of tearing strength of fabric.

Nanostructural Biochemical Modification Of Flax Fiber In The Processes Of Its Preparation For Spinning

Abstract The elaborated principles of nanoengineering of linen textile materials implement the techniques of spatially localized effects of protein catalysts on polymeric cellulose companions with selective splitting of impurity compounds without damaging technologically necessary nano-sized formations of binders in the fiber structure. The ranges of optimal values of the residual content in flax fiber prepared for spinning are identified on the basis of the analysis of the successive stages of enzymatic and peroxide treatments contribution to the breakdown of polymers and the differentiation of the influence of impurities on the yarn technological properties. The recommended level of residual pectin, lignin and hemicellulose (wt. %) is: after enzymatic treatment P1 = 1,0±0,1; L1 = 3,9±0,3; Hc1 = 11,0±1,0; after peroxide bleaching P2 = 0,4±0,05; L2 = 2,3±0,3; Hc2 = 7,5±0,5. The required level of fiber structural modification at the stage of preparing roving for spinning can be achieved through use of protein catalysts whose globule size is 50...100 nm. The use of enzymes with these dimensional characteristics helps to ensure breaking of polymer adhesives on the surface of incrusts and in the areas of intercellular formations, which hinder fiber crushing, without damaging nano-sized binding fractions. The implementation of this method contributes to a significant improvement in the uniformity of structural and physical and mechanical properties of flax yarn. Increase in yarn fineness and strength properties of semi-finished products, as well as improvement of deformation properties and reduction of yarn breakages during the spinning processes are achieved.

Study on the Effect of Different Woven Structures on Physical Properties of Cotton Muslin Fabric

In this paper studies were undertaken to observe the effect of fiber and yarn properties on the properties of cotton Muslin fabric made in Khadi sector. Fine cotton muslin fabrics, which are being produced from Suvin variety of cotton in various parts of the country were analyzed in terms of realization of fiber strength in yarn and yarn strength in fabric. Fine cotton bleached fabrics of three types of weaves namely plain, 1/3 twill and 4 end irregular sateen are prepared out of 2.7 tex unsized yarn and tested with respect to all relevant physical properties.

A new Monte Carlo model for predicting the mechanical properties of fiber yarns

Understanding the complicated failure mechanisms of hierarchical composites such as fiber yarns is essential for advanced materials design. In this study, we developed a new Monte Carlo model for predicting the mechanical properties of fiber yarns that includes statistical variation in fiber strength. Furthermore, a statistical shear load transfer law based on the shear lag analysis was derived and implemented to simulate the interactions between adjacent fibers and provide a more accurate tensile stress distribution along the overlap distance. Simulations on two types of yarns, made from different raw materials and based on distinct processing approaches, predict yarn strength values that compare favorably with experimental measurements. Furthermore, the model identified very distinct dominant failure mechanisms for the two materials, providing important insights into design features that can improve yarn strength.

Combined application of multinozzle air-jet electrospinning and airflow twisting for the efficient preparation of continuous twisted nanofiber yarn

This paper presents a new approach for the mass production of nanofiber yarns, which involves the use of a multinozzle air-jet electrospinning system and airflow twisting. In this system, the aggregation, orientation, and continuous bundling of nanofibers are first achieved by applying the principle of conjugate electrospinning. Three-dimensional highspeed rotating airflow is then applied to continuously twist and spin the nanofibers into yarn. In this study, the mechanisms for formation and aggregation of nanofibers using the new air-jet electrospinning system were analyzed. In addition, numerical simulations of the airflow field within the nozzle were performed to understand the airflow characteristics and to study the effects of airflow twisting on nanofiber spinning. The obtained results indicated that the output of nanofiber bundles for the proposed multinozzle air-jet electrospinning system was able to reach 6.642 g/h. The application of three-dimensional rotating airflow enabled continuous production of twisted nanofiber yarns with favorable orientation and uniform twist distribution. Under an air pressure of 0.3 MPa and at a spinning speed of 132.1 m/s, the twist angle, tensile strength, and elongation of the nanofiber yarn were 65.2 °, 74.23 MPa, and 85.55 %, respectively. Thus, it can be concluded that the proposed spinning tenique is practical and efficient for high-speed and large-scale production of nanofiber yarn.

Gel spinning of PVA composite fibers with high content of multi-walled carbon nanotubes and graphene oxide hybrids

In this report, poly (vinyl alcohol) (PVA) composite fibers with high content of multi-walled carbon nanotubes and graphene oxide (MWCNTs-GO) hybrids were prepared by gel spinning, and were characterized by TGA, DSC, SEM, XL-2 yarn strength tester and electrical conductivity measurement. The total content of MWCNTs-GO hybrids in the PVA composite fibers, which is up to 25 wt%, was confirmed by TGA analysis. The DSC measurement shows that the melting and crystallization peaks decreased after the addition of nano-fillers. This is due to the reason that the motion of PVA chains is completely confined by strong hydrogen bonding interaction between PVA and nano-fillers. After the addtion of GO, the dispersibility of MWCNTs in composite fibers improved slightly. And the tensile strength and Young's modulus increased by 38% and 67%, respectively. This is caused by the increased hydrogen bonding interaction and synergistic effect through hybridization of MWCNTs and GO. More significantly, the electrical conductivity of PVA/MWCNTs/GO composite fibers enhanced by three orders of magnitude with the addition of GO.

UV reflectance attributed direct correlation to colour strength and absorbance of natural dyed yarn with respect to mordant use and their potential antimicrobial efficacy

In this study, an attempt has made to investigate the impact of UV reflectance of un-dyed and dyed cotton yarn on the quantity of natural dyes absorbed by the fibre and observed its colour intensity. The study also provides evidence of the relationship between the UV reflectance and the colour strength of the dyed cotton with respect to mordant. The absorption of dyes on cotton yarns ranged from 5.06 to 34.09% in 5% dye solution of different plant extracts. Experimental data revealed that the higher colour intensity (K/S) corresponded to lower UV-reflectance and higher dye absorption of the dyed yarns. It was demonstrated that the dyed cotton yarns displayed excellent antimicrobial activity against bacterial strain Streptococous pyogenes (reduction rate: 52–61%) and the fungal strain Aspergillus niger (reduction rate: 35–63%) for developing protective clothing. The current findings clearly demonstrate that the extraction of natural colourants from waste leaves and superficial barks of the plants could be a sustainable technology for waste utilization of bio-resources by the small-scale segments as well as the rural weaver's societies for their socio-economic growth.

Effect of transverse compression on the tensile strength of aramid yarns

Effect of transverse compression on the tensile strength of aramid yarns

Cotton Fibre-to-Yarn Engineering: A Simulated Annealing Approach

In this paper we undertake to engineer yarn of predefined strength by choosing suitable raw material and process parameters. In an attempt to achieve a yarn of optimal strength, the constrained optimisation problem is formulated with the relation between raw material and yarn properties. Frydrych’s theoretical model of yarn strength is used for formulation of the optimisation problem. The simulated annealing (SA) method has been used to solve the optimisation problem by researching the best combination of raw material and process parameters that can bring into reality a yarn with the strength desired. The results show that SA is capable of ascertaining a set of parameters that gives the yarn strength desired.

Using artificial neural networks with graphical user interface to predict the strength of carded cotton yarns

Artificial neural networks (ANNs) are used in prediction fields. Yarn strength is one of the most important properties, because it reflects the quality of the yarn. The prediction process of yarn strength is very important from the technology side because many of generated forces in the spun yarns could be given by yarn strength. Data were collected from the United Commercial Industrial Company, Damascus, Syria. Then, artificial neural network algorithm was architected. Several neural networks were architected one of these has been chosen, which contained acceptable network error rate. To deal easily with ANN, a simple graphical user interface has been created. This ANN has been tested on a new sample. Results were compared with the actual results as well as the relationship of Solovev which is allocated to predict the strength cotton yarn. ANN has given more acceptable results than Solovev’s relationship.

Impact of Gin Saw-tooth Design on Fiber and Textile Processing Quality

Toothed gin saws have been used to separate cotton fiber from the seed for more than 200 years. A scientific analysis of saw-tooth design has never been published and the optimum saw-tooth design has not been found. Initial laboratory ginning evaluations of some modern gin saw teeth have shown differences among designs in ginning rate, fiber length measurements, and textile processing quality. The saw gin stand used for testing was a Continental Double Eagle that had been cut down to 46 saws. Four different sets of 16-in diameter, commercially available replacement saws were obtained from independent suppliers. These four sets, along with the standard Continental saw set, were used for five test saw treatments. The test saws varied in the number of teeth per saw from 328 to 352. Testing of the five saw treatments was replicated four times for a total of 20 ginning lots. Each ginning lot was analyzed for raw fiber quality and textile spinning performance. Most of the raw fiber properties were not significantly affected by the saw treatments. However, HVI length and length uniformity after one stage of lint cleaning and seed cotton processing rate were significantly different among saw treatments. The ginning rates varied by 34% from the lowest to the highest at 75% gin stand motor load. The ginned fiber was processed into both open-end and ring-spun yarns. There were few significant differences among saw treatments for the open-end yarn, but there were significant differences for the ring-spun yarn in ends down (a measure of spinning efficiency), yarn evenness, and yarn strength. This indicates that gin saw-tooth design might significantly affect spinning efficiency and yarn quality. Research is currently being done to further understand how gin saw-tooth design affects ginned fiber quality and textile processing quality factors.

Spindle Speed Optimization for Cotton Pickers

Abstract. There is concern that changes to the operating speed and size of spindles on cotton picker harvesters over the years have resulted in a general decrease in cotton fiber quality, especially spindle twists, preparation, and neps. Previous research showed that spindle speeds of 3000 and 4000 rpm had more detrimental effects on picker stalk loss, trash levels in seed cotton, and cotton fiber quality than a spindle speed of 2000 rpm. This study was conducted to check fiber quality effects between 2000 and 2800 rpm in order to further define the optimum spindle speed range. Field tests were conducted for the 2008 and 2009 crop years by the USDA, Agricultural Research Service, Southwestern Cotton Ginning Research Laboratory in Mesilla Park, New Mexico. Three cotton varieties were grown under furrow-irrigated conditions in southern New Mexico and harvested with a modified one-row cotton picker each year using a ground speed of 0.85 m s-1 (1.9 miles h-1) and spindle speeds of 2000, 2200, 2500, and 2800 rpm. The tests were replicated four times. No significant differences in stalk losses in the field were found. Significantly more trash was present in seed cotton picked with spindle speeds of 2200, 2500, and 2800 rpm than in seed cotton picked with a spindle speed of 2000 rpm. Differences in trash content were eliminated by seed cotton cleaning (same for all treatments). HVI classing data showed no significant differences among spindle speed treatments. Differences due to spindle speed for AFIS nep count, short fiber count, trash count, dust count, and seed coat nep count were non-significant at each of the four locations tested in the yarn preparation process. Results from open-end spinning tests, including opening and cleaning waste, total card waste, ends down, yarn strength, yarn elongation, neps, thick places, and thin places showed no significant differences due to spindle speed. Based on these results, the 2000 rpm spindle speed is optimal because trash in the seed cotton is reduced which reduces ginning costs; however; only minimal differences are present at spindle speeds up to 2800 rpm.

Effect of the distance between jet orifice and nozzle Alex on properties of vortex spun yarn

This study focuses on the effect of various distances between the jet orifice and the nozzle Alex on the properties of the vortex spun yarn. Four levels of the distance are designed within certain range. Building three-dimensional computational fluid dynamics models, we use the method of numerical simulation to calculate the inner fluid field of nozzle. The results showed that the distance typically affected the airflow movements, particularly in tangential velocity, and the smaller d is beneficial to diffuse the airflow uniformly and to improve the quality of vortex spun yarn. The corresponding experiments have been carried out. In this paper, 100% viscose drawing slivers are spun into vortex spun yarn, and their physical properties are tested. Spinning experiment results prove that when the distance is minimum under the condition of avoiding the high-speed airflow shooting out from the jet orifices colliding with the cone body, the yarn strength reaches the maximum value, while the unevenness of breaking strength meets the minimum, and the other yarn properties are superior, which shows a good agreement with the simulation results.