Rayon Yarns Research Articles

Elasto-viscoplastic model for rayon yarns

AbstractIn this paper we develop a new model for the simulation of the mechanical behavior of rayon twisted yarns, at macroscopic level. A yarn with its continuous filaments is represented by an equivalent three-dimensional solid of cylindrical shape, discretized by finite elements, with properly defined local anisotropic material properties. The new constitutive model, inspired by experimental results on rayon untwisted yarns, is formulated in the framework of the thermodynamics of irreversible processes and includes visco-elastic and visco-plastic dissipation mechanisms. The effect of twist is taken into account by including the direction of the fibers in the free energy definition. The overall model is validated comparing numerical and experimental results on twisted rayon yarns.

The Use of Composite Textile Techniques as Upholstery Fabric for Interior Furnishing

This is an art studio Practice-based study that employed the creativity of using Ikat technique, Embroidery technique, leather material, and woven Kente fabric from cotton and rayon yarns to create the design for the production of artistic Upholstery for interior furnishing, using yarn dyeing, traditional loom, and sewing and embroidery techniques in textiles. While plain cotton and synthetic materials for Sofa production abounds in Ghana, the study found the combination of Ikat technique, embroidery, woven kente and leather as a composite material in the production of upholstery in Ghana not exploited in the Upholstery industries. Descriptive and studio/practice-based research methods were employed under the qualitative research approach as the research design for the study. The study presents systematic processes involved in the production of upholstery design for sofas. The study proved that the medium chosen is good for upholstery design for sofas in interior furnishing. Weaving techniques were used to generate a well-defined weave structure from dyed yarns which was augmented by leather material woven in a twill structure with embroidery stitches. All the techniques combined yielded a good design for Upholstery.

An Innovative Approach to Producing Foot and Armrest with Kente and Leather for Interior Furnishing

This is an art studio Practice-based study that explored the creativity of using leather and woven Kente fabric from cotton and rayon yarns as materials for creating foot and arm-rest for interior furnishing, using sewing and embroidery techniques in textiles. While plain cotton and synthetic materials for foot and arm-rest abound in Ghana, the study found the combination of woven kente as traditional Ghanaian fabric and leather in the foot and arm-rest production as not exploited in the textile industries. The study proved that woven Kente fabric from cotton and rayon yarns; with leather are good materials for creating foot and arm-rest for interior furnishing. The fabric weaving techniques generated a well-defined weave pattern which was augmented by leather material woven in twill structure and embroidery technique, good for producing foot and arm-rest for interior furnishing.

The effect of top roll defects on dyh5000 toyoda hara finisher draw frame on sliver unevenness at pt xyz

PT. XYZ is one of the spinning companies that produce cotton carded and Rayon yarn. One of the machines used in the yarn spinning process is the finisher draw frame. In the finisher draw frame process, slivers was produced. To maintain stability of the resulted sliver remain standard, it is necessary to check the sliver number (Ne1) and unevenness of the sliver (u%) with the uster uneveness tester tool. On the finisher draw frame, problems were often found, one of these was unevenness value (u%) that exceed the standard. The purpose of this study was to see the effect of top roll defects on unevenness (u%) and how to overcome these defects. After observing the sliver and testing it on the finisher draw frame, the slivers was tested using an uster unevenness tester 4. The results were not in accordance with company standards, which are 2.50% to 2.90%. The causes of the defect include: lapping material, use of equipment during lapping cleaning. To overcome the problem of defects, repairs were made by grinding the top roll or replacing it with a new top roll. After repairs or replaced with a non-defective top roll, the result is 2.82% and 2.88%

Protection and the British rayon industry during the 1920s

The Finance Act of 1925 imposed upon rayon yarn an excise duty of 1 s. per lb. and an import duty of 2 s. per lb. This article argues that the difference between the excise and import duties was not intended as classic protection. Rather, the difference was intended only to indemnify British producers for the excise-wrought decline in domestic consumption by means of an offsetting reduction of imports. This article then estimates that, had the rayon duties been removed in 1926, the share of imports in Britain’s growing consumption of rayon yarn would have increased from one-tenth to at least one-quarter. Trade policy had secured the domestic market for British rayon firms prior to the formation of an international cartel in 1927. More broadly, this article instantiates that trade policy was considerably distorting the British market for manufactured goods well before the landmark Import Duties Act of 1932.

Aerobic biodegradation in freshwater and marine environments of textile microfibers generated in clothes laundering: Effects of cellulose and polyester-based microfibers on the microbiome

The aerobic biodegradation of common textiles that shed microfibers during laundering was evaluated under the action of microbes found in the environment, such as lake and seawater, and activated sludge at a low concentration from a wastewater treatment plant (WWTP). Under these conditions, the biodegradation potential was the same in all the experiments: Microcrystalline Cellulose (MCC) > Cotton > Rayon > Polyester/Cotton ≫ Polyester. Nevertheless, for cotton and rayon yarns, >70% biodegradation was achieved with activated sludge at low concentration and lake water, whereas in seawater, about 50% degradation was reached. Polyester did not appreciably degrade. The biodegradation results herein indicate potential not absolutes in nature. The bacterial diversity analyses in the different biodegradation inoculums show that there are distinct bacterial communities related to the assimilation and mineralization of complex carbohydrates that were promoted with the cellulosic MCC, cotton, and rayon samples different than the polyester sample.

Mechanics for the Adhesion and Aggregation of Red Blood Cells on Chitosan

AbstractHemostasis, a process which causes bleeding to stop, can be enhanced using chitosan; but the detailed mechanism is unclear. Red blood cells (RBCs) adhere to chitosan because of their opposite charges, but the adhesion force is small, 3.83 pN as measured here using an optical tweezer, such that the direct adhesion cannot be the sole cause for hemostasis. However, it was observed in this study that layer structures of aggregated RBCs were formed next to chitosan objects in both static and flowing environments, but not formed next to cotton and rayon yarns. The layer structure is the clue for the initiation of hemostatsis. Through the supporting measurements of zeta potentials of RBCs and pH's using blood-chitosan mixtures, it is proposed here that the formation of the RBC layer structure next to chitosan objects is due to the reduction of repulsive electric double layer force between RBCs, because of the association of H+deprotonated from chitosan with COO−on RBC membrane, under the DLVO (Derjaguin-Landau-Verwey-Overbeek) theory. The results are beneficial for designing effective chitosan-based wound dressings, and also for general biomedical applications.

Structural design and physical characteristics of modified ring-spun yarns intended for e-textiles: A comparative study

E-textiles based on yarn-based sensors have been a topic of intense research. In our previous paper, a straightforward way for fabricating tri-component elastic-conductive composite yarns (t-ECCYs) with a unique architecture applicable to yarn-based sensors was proposed using a modified ring-spinning frame. Herein, a comparative analysis of the physical characteristics of t-ECCY, bi-component elastic composite yarn (b-ECY), bi-component conductive composite yarn (b-CCY), and single rayon yarn (s-RY) are presented, in detail, in terms of tensile behavior, elastic recovery, electrical resistance, unevenness, and hairiness. In particular, a systematic study of the tensile and conductive properties of yarns appropriate for e-textiles, that is, t-ECCY and b-CCY, are highlighted. In addition, a non-invasive structure verification technique is conducted to identify the dispositions of constituents inside the yarn. It is found that the t-ECCY exhibits a remarkable improvement over the other yarns, having robust tensile properties, super elasticity, stable electrical durability, lower unevenness, and hairiness. A simple tensile model has been proposed to predict the t-ECCY’s tensile strength, and the substantial improvement in the tensile properties of t-ECCY compared with the b-CCY can be associated with the distinctive yarn structure. The stretch-deformation mechanism of coils in the t-ECCY is, initially, separation of adjacent surfaces of coils and gradual unwinding till free. Benefiting from its superior conductivity and elasticity after single/cyclic stretch tests as well as other properties, the t-ECCY itself can serve as a sensing element, which could be a highly valuable use for specific purposes in smart textiles.

CAD/CAE for stress–strain properties of a wide range of multifilament twisted man-made filament yarns

In a previous paper, the computer aided design (CAD)/computer aided engineering (CAE) approach was presented and compared via the stress–strain curves of high-tenacity rayon yarn and the energy method. The maximum stress–extension curves showed very good agreement with experimental results and were more accurate than the previous methods. In this paper, the CAD/CAE method is considered in relation to multifilament yarn, which is equally applicable to a wide range of man-made filament yarns from nine material types. The results of this prediction model were compared with the stress–strain curves of experimental results and the energy method. The maximum stress–extension curves showed very good agreement with the experimental results except for the high-tenacity Terylene and Fortisan. The reasons for the poor agreement between the experimental and predicted curves are discussed. The breaking points obtained with this method are also compared with experimental results and discussed.

Property Evaluation of Functional Thermal-Regulating/Wicking Conductive Knitted Fabrics

This research focuses on making double-layer complex wrapped yarn using stainless steel fiber (S), rayon yarn, and PET bamboo charcoal yarn in rotor twister. During the process, the twisting speed of the rotor twister was changed. The functional complex thermal-regulating/wicking conductive wrapped yarn of different twisting speeds (2~6 turns/cm) were fabricated using the Fully Computerized Hosiery Machine. The effects of different twisting speeds on the far-infrared emissivity, air permeability, and water absorption of the functional complex thermal-regulating/wicking conductive wrapped yarn were discussed. In the end, the functional knitted fabrics and hosiery with thermal-regulating/wicking conductive properties were made.

CAD/CAE for stress–strain properties of multifilament twisted yarns

A method is presented for modeling the tensile behavior of multifilament twisted yarns. A filament assembly model and a computer-aided design/computer-aided engineering (CAD/CAE) approach are proposed for the tensile analysis. The geometry of the twisted yarn and the nonlinear filament properties were considered. The finite element method (FEM) and large deformation effects were applied for computation of the stress–extension curves. Ideal yarn structures of five layers with different twist angles were simulated to predict the tensile behavior of each filament and each layer. The stress acting on the filaments after yarn extension could be directly analyzed by the FEM. The stress distribution in the filaments showed that the highest stress regions were located at the filament in the center of the yarn and decreased slightly to the yarn surface. The stress–extensions of the filaments were converted to yarn tensile behavior that is shown in terms of the maximum and average stress–extension curves. The results of this prediction model were compared with the stress–strain curves of high-tenacity rayon yarn and the energy method. The maximum stress–extension curves showed very good agreement with experimental results and are more accurate than those obtained by previous methods.

Preparation of Eco-friendly and High Strength Paper for Viscose Rayon Yarn

ABSTRACT Because of acute or chronic intoxication by carbon disulfide, viscose rayon industry is strictly subjected to environment regulatory approval. Recently, non-wood fibers are frequently considered as a raw materials for the manufacture of specialty paper for the higher physical strength and functionality. Among the non-wood fibers, hemp bast fiber is one of the most widely used materials in viscose rayon yarn industries. In this study, the handsheet for manufacturing the viscose rayon yarn was prepared with wood pulp fibers and hemp bast fibers. The proper mixing ratio of wood fibers and hemp bast fibers with dry-strength agent and nano-celluloses was analysed in terms of physi-cal and mechanical strength of sheet for viscose rayon yarn. The papermaking conditions for high mechanical strength of sheet were obtained by mixing the SwBKP and HwBKP fibers with freeness level of 200 mL CSF. The dual polymer system by controlling the ad-dition ratio of PVAm and anionic PAM was also important. The addition of nano-cellulose into wet-end furnishes increased the physical strength of sheet, and improved the paper structure for the production of viscose rayon yarn.Keywords: Hemp, viscose rayon yarn, non-wood fibers, PVAm, A-PAM, nanocellulose

Robust and Accurate Closed-Loop Control of McKibben Artificial Muscle Contraction with a Linear Single Integral Action

We analyze the possibility of taking advantage of artificial muscle’s own stiffness and damping, and substituting it for a classic proportional-integral-derivative controller (PID) controller an I controller. The advantages are that there would only be one parameter to tune and no need for a dynamic model. A stability analysis is proposed from a simple phenomenological artificial muscle model. Step and sinus-wave tracking responses performed with pneumatic McKibben muscles are reported showing the practical efficiency of the method to combine accuracy and load robustness. In the particular case of the McKibben artificial muscle technology, we suggest that the dynamic performances in stability and load robustness would result from the textile nature of its braided sleeve and its internal friction which do not obey Coulomb’s third law, as verified by preliminary reported original friction experiments. Comparisons are reported between three kinds of braided sleeves made of rayon yarns, plastic, and thin metal wires, whose similar closed-loop dynamic performances are highlighted. It is also experimentally shown that a sleeve braided with thin metal wires can give high accuracy performance, in step as in tracking response. This would be due to a low static friction coefficient combined with a kinetic friction exponentially increasing with speed in accordance with hydrodynamic lubrication theory applied to textile physics.

Adsorption Efficiency for Adsorption of a Series of Oligomer Resins on Reinforcing Yarns

Using a model approach, we consider the adsorption contribution to the interaction between oligomer resins (ED-20, PN-15, SF-342A) with reinforcing yarns (viscose rayon, basalt, and glass). We show that the efficiency of interaction between the yarns and the indicated resins decreases in the series viscose rayon yarn > glass yarn > basalt yarn. In this case, the viscose rayon yarn is the most thermodynamically feasible for adsorption of resins, while the basalt yarn is the most kinetically feasible.

Mechanical crimp texturizing of non-thermoplastic viscose rayon yarn

There are technological limitations in the processing of smooth, slippery and rather flat multifilament viscose rayon yarn. The present work describes a shorter route for viscose rayon modification through mechanical crimp texturizing. Texturizing was performed with different pre-twists and optimized texturizing twist. This work describes a shorter and cost effective route for viscose rayon modification through mechanical crimp texturizing. The prepared texturized viscose rayon yarn has achieved the desirable structural characteristics of spun yarn as depicted in SEM micrographs. The textured yarn has retained an almost identical fineness with the parent yarn. Unlike air jet texturizing, mechanical crimp texturizing has benefits in terms of retro-processing of costlier viscose rayon yarn. Although it was textured, it has not shown any significant drop in tenacity and, apart from that, shows enhanced the elongation property compared to the parent yarn.

한지와 레이온 복합사 편성물의 물성

This study presents basic knitted fabric data on the use of ply yarn with rayon yarn and eco-friendly/ high-valued Hanji yarn. Physical properties (gauge, thickness, burst strength, air permeability, stiffness, Qmax, dimensional stability and surface image) of Hanji 100%, rayon 100% and Hanji/rayon 50:50 knitted fabrics are investigated. The results are as follows. Course direction of gauge decrease in the following order: rayon 100% > Hanji/rayon 50/50 > Hanji 100%. In addition wale direction of gauge decrease in the following or- der: Hanji 100% > Hanji/rayon 50/50 > rayon 50/50. Thickness and air permeability decrease in the follow- ing order: Hanji 100% > Hanji/rayon 50/50 > rayon 100%. Burst strength decrease in the following order: rayon 100% > Hanji 100% > Hanji/rayon 50/50. Stiffness and Qmax decrease in the following order: rayon 100% > Hanji/rayon 50/50 > Hanji 100%. Laundry for dimensional stability is knitted fabric with Hanji/ray- on 50/50 than rayon 100% and Hanji 100% improved using neutral detergent and stable at 20 o C. From sur- face image observation, the cracks of Hanji 100% and fibrils of rayon 100% decrease when using knitted fabric with Hanji/rayon 50/50.

Development of microporous activated carbon using a polymer blend technique and its behavior towards methylene blue adsorption

Coloured wastewater is released as a direct result of the production of dyes as well as from various other chemical industries. Many dyes and their breakdown products may be toxic for living organisms. Activated carbon is one of the best materials for removal of dyes from aqueous solutions. The present study describes the adsorption behaviour of methylene blue dye on three microporous activated carbons, where two samples (AC-1 and AC-2) were pre- pared by a polymer blend technique and the other is a microporous activated carbon (ARY-3) sample from viscose rayon yarn prepared by chemical-physical activation. The effects of contact time and activated carbon dosage on decolourisation capacity have been studied. The results show that activated carbon having mixed microporosity and mesoporosity show tremendous decolourisation capacity for methylene blue. In addition, the activated carbon in the powder form prepared by the polymer blend technique shows better decolourisation capacity for methylene blue than the activated rayon yarn sample.

A new computer geometric modelling approach of yarn structures for the conventional ring spinning process

A new computer modelling approach for three-dimensional yarn structures produced by the conventional ring spinning system is presented. The concept of virtual locations for modelling yarn cross section is extended. Virtual locations are ring configuration with ellipsoid shapes defined by yarn-twist level in each ring layer. A mathematical model based on migrating helix is developed. Fibre migration is governed by geometric and tension mechanisms. The migration parameters include twisting tension, migration period and amplitude. The initial phase and frequency of migration pattern are used as the parameters of fibre migration. Based on the results obtained from the virtual locations concept and mathematical model of twist, a computer-aided design modelling approach for fibre assemblies is presented for geometric and visual simulation of yarn structures. The fibre paths in each interval between two successive cross sections are approximated by non-uniform rational B-spline curves. The geometric model of each fibre is created by sweeping a closed curve along a centreline path. The new model is validated by using process parameters of spun rayon yarn.

Computer Aided Geometric Modeling of Twist Fiber

Problem statement: The objective of this study is to compare the methods for approximating the positions of twist fiber in yarn structures. Computer Aided Design (CAD) is applied using parametric equation, spline curve and NURBS curve. The ideal twist fiber and fiber migration are studied in 3 dimensions. Approach: The fiber positions in yarn structures were measured by trace fiber technique. The twist fiber in rayon yarn with 2.1, 3.0 and 6.0 twist factors was used as examples. The geometrical properties of twist fiber including curvature and torsion were applied in the analysis of all twist fiber examples. Each position was approximated along the length of yarn and then graphical representations of fiber are shown. Results: For ideal twist yarn, using parametric equation gives a smoother or better curve than when using the spline and NURBS curves. However, in the case of fiber migration, continuity of spline and NURBS curves are smoother than that of parametric equation. Conclusion/Recommendations: According to the comparison of the approximation method, parametric equation is most suitable for geometric modeling of ideal twist fiber, whereas the spline and NURBS curves were recommended for approximating the position of migrating fiber.

Manufacturing Process and Property Evaluation of Functional Composite Yarn-Dyed Woven Fabrics Made from Bamboo Charcoal/Stainless Steel and TPU

Recently, development of technology increases human life quality and gradually raises the value of health protection in human’s concept. Bamboo has multi-functional including far infrared radiation, deodorization and anion generation. Therefore, bamboo charcoal has been widely used in textile industry. Moreover, development of technology also increased the electromagnetic hazard in human’s daily life. This study aims to develop a manufacturing process of functional composite yarn-dyed woven fabrics. In the manufacturing process, the materials included pure cotton yarn, stainless steel fiber(called metallic yarn) and viscose rayon yarn containing bamboo charcoal (called bamboo charcoal yarn) were used for making the bamboo charcoal/stainless steel composite woven fabric. The composite woven fabrics were woven by using same warp yarn and two kinds of weft yarn that contained bamboo charcoal and stainless steel. The composite fabrics had two different structures. Those fabrics were changed the order of bamboo charcoal yarn and metallic yarn. The ratios of weft yarn were 1 end of bamboo charcoal yarn to 1 end of metallic yarn and 3 ends of bamboo charcoal yarn to 1 end of metallic yarn. Furthermore, the fabrication of composite fabrics that included plain, 2/2 twill and dobby were changed. The composite woven fabrics were finished and laminated by TPU film to enhance the waterproof and vapor permeable functions. The laminated composite fabrics were evaluated by far-infrared coefficient, anion generation rate, water vapor permeability, water resistance, surface electric resistance and electromagnetic shelter property to obtained optimal manufacturing process.