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This study aims to investigate the effect of alkalization and chemical coupling methods on the surface and adsorption properties of waste cotton and cotton/polyester yarns. The simple and cheap alkali treatment was performed using 10% and 18% NaOH solution, while the chemical coupling method involved combining cotton and cotton/polyester yarns and fly ash, using sodium carboxymethyl cellulose and sodium alginate as binders. Morphological and surface characteristics of unmodified and modified cotton and cotton/polyester yarns were analyzed by scanning electron microscopy and Fourier transform infrared spectroscopy, while adsorption properties were assessed by the removal of lead and cadmium ions from aqueous solution. It was found that chemical modification with 18% NaOH solution positively affected the adsorption properties of only cotton yarns, increasing the removal efficiency of lead ions up to 75%. On the other hand, modification with fly ash improves the adsorption properties of both, cotton and cotton/polyester yarns, increasing the efficiency in removing lead ions by using sodium carboxymethyl cellulose, and cadmium ions by using alginate as a binder. Using the chemical coupling method, effective adsorbents are obtained starting from waste yarn, which gives it added value, the amount of non-degradable waste material can be reduced and the criteria of a cleaner environment and circular economy can be met.

The use of tungsten fiber-reinforced tungsten composites (Wf/W) has been demonstrated to significantly enhance the mechanical properties of tungsten (W) by incorporating W-fibers into the W-matrix. However, prior research has been restricted by the usage of single fiber-based textile fabrics, consisting of 150 µm warp and 50 µm weft filaments, with limited homogeneity, reproducibility, and mechanical properties in bulk structures due to the rigidity of the 150 µm W-fibers. To overcome this limitation, two novel textile preforms were developed utilizing radial braided W-yarns with 7 core and 16 sleeve filaments (R.B. 16 + 7), with a diameter of 25 µm each, as the warp material. In this study, bulk composites of two different fabric types were produced via a layer-by-layer CVD process, utilizing single 50 µm filaments (type 1) and R.B. 16 + 7 yarns (type 2) as weft materials. The produced composites were sectioned into KLST-type specimens based on DIN EN ISO 179-1:2000 using electrical discharge machining (EDM) and subjected to three-point bending tests. Both composites demonstrated enhanced mechanical properties with pseudo-ductile behavior at room temperature and withstood over 10,000 load cycles between 50–90% of their respective maximum load without sample fracture in three-point cyclic loading tests. Furthermore, a novel approach to predict the fatigue behavior of the material under cyclic loading was developed based on the high reproducibility of the composites produced, especially for the composite based on type 1. This approach provides a new benchmark for upscaling endeavors and may enable a better prediction of the service life of the produced components made of Wf/W in the future. In comparison, the composite based on fabric type 1 demonstrated superior results in manufacturing performance and mechanical properties. With a high relative average density (>97%), a high fiber volume fraction (14–17%), and a very homogeneous fiber distribution in the CVD-W matrix, type 1 shows a promising option to be further tested in high heat flux tests and to be potentially used as an alternative to currently used materials for the most stressed components of nuclear fusion reactors or other potential application fields such as concentrated solar power (CSP), aircraft turbines, the steel industry, quantum computing, or welding tools. Type 2 composites have a higher layer spacing compared to type 1, resulting in gaps within the matrix and less homogeneous material properties. While type 2 composites have demonstrated a notable enhancement over 150 µm fiber-based composites, they are not viable for industrial scale-up unlike type 1 composites.

Electronic yarns contain electronic components which are fully embedded into the conductive yarn’s structure before manufacturing smart textile garments or fabrics. To accept comprehensively the electronic textiles, it is essential to integrate the electronic components into/onto the conductive textile yarn without compromising the quality of the textile substrate. Therefore, one of the solutions is to create flexible and stretchable conductive yarn that contains a small surface-mounted electronic component embedded in the fibers of the conductive yarn. The purpose of this research work is to manufacture and subsequently evaluate the physical and electromechanical properties of amber strand (Toyobo’s p-phenylene benzobisoxazole fiber zylon) yarns with embedded surface-mounted device components. Using a benchtop reflow-soldering machine, the surface-mounted device component was successfully inserted into the amber strand conductive yarn. Then the developed electronic yarn was coated using thermoplastic polyurethane for encapsulation purposes. Furthermore, reliability tests of the electrical and mechanical properties of the electronic yarn (tensile strain and washing) were carried out. From the results it can be seen that the developed thermoplastic polyurethane encapsulated electronic yarn had a tensile strength of 37.38 N with a 4.1 mm extension. Furthermore, the relationship between the strain and washing action on the electrical resistance of the developed electronic yarn was experimentally investigated. The analytical finding shows that mechanical stress and laundry washing had a significant influence on the electrical resistance of the electronic yarn.

The ring spinning is the end of the stages of the cotton yarn spinning by traditional methods Before Yarn winding Process, and is characterized by being one of the best methods used to produce thin yarns with high durability of short fibers, it can also produce cotton yarns from No. 4 to No. 240 E, and due to the multiplicity Types of cotton material, and multiple sources, the research was conducted to unclear the impact of the use of different types of cotton on the quality of yarns produced by The ring spinning of yarn, and this study was conducted with the aim of the possibility of producing cotton yarns with different materials and types with different number ring spinning system with better properties in functional performance In the production of (12) samples of cotton yarn with (4) different cotton materials (Giza 86, Giza 90, Greek cotton, Burkina cotton),and (3) cotton yarns of different number (16/1, 20/1, 24/1), and conducted various tests (RKM, elongation, Naps, thick places, thin places and the percentage of irregularities on the yarns to illustrate the effect of using different types of cotton material on the yarns produced in the study, and the results after statistical analysis showed a clear difference in many tests, which shows the obvious effect of the research variables on the produced yarns, and the importance of research in determining the best Types of cotton material used in the production Yarns of different numbers, which are produced by ring spinning system, reflected on job performance, and the results were within RKM values for Giza 86 cotton reached the highest, while it came for the lowest Burkina cotton material, The elongation values for the highest Greek cotton, while the elongation values For the lower Burkina cotton material, The values of Naps of the highest Burkina cotton material, while the value of the cotton material came Giza 86 least, Values came in the thickest places of the highest Burkina cotton material, while the values of the cotton material Giza 90 were lowest , The values of the thin places of the highest Greek cotton material, while the value of the thin places of the lowest the cotton came to Giza 86, and Giza 90, , The percentage of irregularity of the highest Burkina cotton material was achieved, while the cotton material came to Giza 86 the least.

Mass transport in textiles is crucial. Knowledge of effective mass transport properties of textiles can be used to improve processes and applications where textiles are used. Mass transfer in knitted and woven fabrics strongly depends on the yarn used. In particular, the permeability and effective diffusion coefficient of yarns are of interest. Correlations are often used to estimate the mass transfer properties of yarns. These correlations commonly assume an ordered distribution, but here we demonstrate that an ordered distribution leads to an overestimation of mass transfer properties. We therefore address the impact of random ordering on the effective diffusivity and permeability of yarns and show that it is important to account for the random arrangement of fibers in order to predict mass transfer. To do this, Representative Volume Elements are randomly generated to represent the structure of yarns made from continuous filaments of synthetic materials. Furthermore, parallel, randomly arranged fibers with a circular cross-section are assumed. By solving the so-called cell problems on the Representative Volume Elements, transport coefficients can be calculated for given porosities. These transport coefficients, which are based on a digital reconstruction of the yarn and asymptotic homogenization, are then used to derive an improved correlation for the effective diffusivity and permeability as a function of porosity and fiber diameter. At porosities below 0.7, the predicted transport is significantly lower under the assumption of random ordering. The approach is not limited to circular fibers and may be extended to arbitrary fiber geometries., German Research Foundation (DFG)

Knowing the reflection, transmission, and absorption properties of the yarns from which the woven fabric is made, prediction of a fabric’s UV-protective properties is simple. Using the geometrical properties of monofilament yarns and fabrics, which were determined optically, and following the cover factor theory, we have determined the areas of fabrics covered with no yarns, only one yarn, and two yarns. From a special selected set of high-module polyethylene terephthalate (PET) monofilament materials (e.g., fabrics), we have elaborated a method for determining the reflection, transmission, and absorption of yarns. By first defining the differently covered areas of fabrics, we were able to use them in a mathematical model for calculating and predicting the UV-protective properties of the fabrics. The calculated and measured values of the UV-protective properties of the selected test fabrics were highly correlated, with a correlation coefficient >0.98.

In addition to the lack of research on the effect of structural factors and the different seams process on the functional performance of the upholstery fabrics, this study was conducted to identify the effect of some structural factors for these fabrics. Synthetic yarns such as (polyester texture, polyester flat, polypropylene) used as wefts, densities of these wefts (15-20-25) per cm, and some types of seams during fabric production (simple seam - compound seam - French seam), For the purpose of producing furniture fabrics with more characteristics suitable for the functional performance produced for it (upholstery fabrics) using some structural structure variables (different yarns of different density) and different seams, with consistency of fabric and texture composition used, showing the importance of research in determining the most important factors affecting Producing distinct types of upholstery fabrics suitable for efficient use as upholstery fabrics, and their reflection on their functional performance. The applied statistics were used to compare the above variables, and the statistical radar was used to select the best research samples produced after the mechanical tests on the finished products. There was a clear variation in the test results of the samples under study (tensile strength, friction resistance and tear resistance), which showed a direct effect of the materials and the density of the wefts and the quality of the sewing seams on the different characteristics of the functional performance of the fabrics produced, Of the final product1- Polypropylene yarns achieved the highest values for tensile strength and tear resistance, while texture polyester achieved the lowest values for these properties in the produced fabrics.2- Polypropylene and flat polyester yarns achieved the highest values for friction resistance, while texture polyester yarn achieved a lower value for friction properties.3- (25)weftcm achieved the highest values of the properties of tensile strength and resistance to tear, while (15)weftcm the lowest values of these properties, in the fabrics produced.4- Polypropylene yarns achieved the highest values for the strength of the sewing strength, while the polyester yarn was the least value for the strength of the sewing strength.5- The composite (English) seam achieved the highest values of the sewing tensile strength, while the basic seam achieved the lowest values of the strength, and achieved the French seam intermediate values between the two mentioned above.6- The highest sewing strength for the best research samples were all for the English composite seam.

In this experimental study, it is investigated, comparatively, the effect on abrasion resistance of the presence of different type of yarns in the structure of knitted fabrics, used for mattress covers. The most significant problem is abrasion wear, which reduce the product 's life and quantify the fabric’s durability under repetitive friction. Complex knits, with various fibrous compositions, and different masses, were subjected to rubbing wear, tested on the NU-Martindale device, then the samples were microscopically evaluated. The results demonstrated the influence of raw material and the number of friction cycles until the material fails. The polyester and viscose textile support showed the highest friction wear resistance. There were presented: the samples subjected to tests, the decrease of the abrasion resistance after the friction tests, the microscopic aspects and the mass loss of the degraded samples. Future studies will also investigate other physico-mechanical characteristics of these types of products with the most demanding requirements that offer high durability and performance.

Auxetic materials, including textiles, exhibit a negative Poisson’s ratio (NPR), which is of interest for many applications. This research aims to optimize the structural parameters of helical auxetic yarns (HAYs) and to evaluate the auxetic performance of these yarns. The research reports on the improvement of auxetic yarn quality and the yarn auxeticity through studying the effect of helical angles, diameter ratio and tensile moduli of the two plies, as well as the binder filament feeding. The maximum NPR of the optimized auxetic yarns was experimentally achieved as low as –9.6, with the helical angle of around 14.0° on average using the optimal machine setting. The optimized yarn parameters enabled the making of high-quality auxetic yarns with a wider range of machine settings than before. In parallel, theoretical and numerical studies were carried out for the engineering design of auxetic yarns, which enabled comparisons among the experimental results, calculated results and results from finite element analysis. The comparison showed that a lower initial helical angle, higher tensile modulus of the wrap ply and lower tensile modulus of the core ply led to a higher auxetic effect. A new finding is reported in that a concave relationship between the diameter ratio and the NPR was discovered. The results of this study could assist researchers in producing HAYs, and this type of HAY could be used for many potential applications, such as filtration and impact protection.

Carbon nanotubes and copper composites have long been predicted as new conductors that may benefit from the high conductivity of copper and the lightweight and very high ampacity of carbon nanotubes. One of the key challenges has been to integrate Cu with CNTs and form a free-standing composite wire. We have achieved this by first making a CNTs filament using high concentration (20 g L-1) CNTs dispersion, an acid-free wet spinning process and then by replacing the polymer with copper using heat based polymer decomposition and periodic pulse reverse electroplating. It has been demonstrated that indeed the specific conductivity and the current-carrying capability (or ampacity) are increased manifold. MWCNTs/Cu composite wires developed in this paper have electrical conductivity σ ~ 5.5 ×105 S cm-1. These MWCNTs/Cu wires are 2/3rd the weight of bulk Cu wires. Their specific electrical conductivity is σρ~ 9.38 ×104 S cm2 g-1 which is 45 % higher than International Annealed Copper Standard (IACS) Cu. These composite wires have an ampacity of A~ 20 ×105 A cm-2 and 4×105 A cm-2 for 1.5 mm and 17 mm gauge length wires respectively, which is 4 to 6 times higher than pure Cu depending on the wire lengths. MWCNTs volume percentage in the MWCNTs/Cu wire is about 40%.

The fabrics with longitudinal stripes have become more common both by their structure and diversity of appearance, and also the products made of them, this being the reason they occupy an important place in fabrics production. Associating links with equal or different average float produces a profound change in the internal fabric structure, giving it a permanent and stable character in stripe appearance. The stripe effect obtained by weaving technology provides stripping stability to the stripes, both in the humid-thermal finishing processes and in the current maintenance, in the wearing process (repeated washings). Also due to their structure, striped fabrics obtained by weaving technology can not be replaced by other fabrics whose stripes are obtained by other methods and technologies. This is the reason why, in most cases, striped fabrics obtained by weaving technology are preferred, and not striped fabrics obtained by other processes, such as printing. From the point of view of the structure, the particularities of striped fabrics obtained by the weaving technology, consist in the way the basic parameters - the connection, the density and the fineness of the yarns, as well as the auxiliary parameters - the curling degree, the dimensional change of the threads by integrating it into the fabric, influence their internal structure. The relationship of the longitudinal strip line depends on the fundamental diagonal link ratio, if it is the even or odd number, and the number of (Xi) lines in the stripe with weft and warp effect.

Electronic textiles (e-textiles) and wearable computing have been emerging increasingly during the last decade. Since the market interest and predictions have grown, the research into increasing reliability and durability of wearables and e-textiles is developing rapidly. The washability of different integration methods and resistance to mechanical stress are the main obstacles being tackled. However, the freedom of movement and overall comfort is still often overlooked during the development phase. It is essential to see the e-textile product as a whole and consider several aspects of user experience. This work will focus on developing and improving the thermoplastic polyurethane (TPU) lamination integration method for e-textiles. In the work, a stretchable copper-polyimide based circuit was laminated onto knit fabric using various TPU films and stacks. The study shares measurable characteristics to determine which material assembly and design would ensure the highest durability for the electronics part without losing its original textile softness, flexibility and stretchability.

One of the basic conditions required of yarns is to have enough tensile strength to allow them to be turned into textiles and also to give the final product durability. During processing, threads are subjected to various unavoidable forms of mechanical stress, simple or compounded, but the amount of stress can be kept under control by adjusting the corresponding operating parameters (speed, gauges, push force on the cylinders of the rolling train etc.). The values of the operating parameters of the spinning operation are set so as to obtain uniform products in large scale production, but also to ensure the preservation of the properties of the fibers and yarns, for further processing. To this end we analyzed the tensile strength of three batches of 100% wool yarn meant for knitting, from three different geo-climatic areas. These are fine woolen yarn of 25 tex and torque of 620 twists/meter. The study of the tensile strength was carried out using a Uster R Tensojet 4 (UTj4) tension meter, analyzing ten samples of 500 m from each batch. The statistical and mathematical processing of the data obtained after analyzing the samples indicated that the yarns from South Africa have better tensile strength and a lower mechanical impedance variation coefficient than yarns from Asia and England.

It is well known from the classical torsion theory that the cross section of aprismatic beam subjected to end torsional moments will rotate and warp inthe longitudinal direction. Rotation is depicted through the angle of twist perunit length and depends in general on the position along the length of thebeam, while the warping function addresses the longitudinal distortion of theunrotated cross sections. In the present study, we consider a prismatic beamthat possesses an initial twist which is constant along its length. A thermalfield is present along the beam and its ends are loaded with axial forcesand torsional moments. The governing equilibrium equations and the correspondingboundary conditions were obtained using an energy variationalstatement. A one-dimensional gradient thermoelastic analogue is developed.The advantageous aspect of the present study is that the additional (andpeculiar) boundary conditions required by the gradient elasticity theory andthe related microstructural lengths, analogous to micromechanical lengths,emerge in a natural way from the geometrical characteristics of the beam crosssection and the material properties. We have examined various examples withdifferent cross sections and loads to demonstrate the applicability of the modelto the design of special yarns useful in smart textiles and thermally activatedmicrodrilling actuators.

International audience; Plant fiber properties, such as morphological and mechanical, are characterized by a large dispersion. Thereby, a statistical analysis is needed to obtain consistent results. An experimental study, conducted on 50 flax yarns, shows that the flax yarn properties (Young's modulus, tensile strength and diameter) follow Gaussian distributions. This approach is obviously reliable, however time-consuming, to get relevant information. An alternative could be the identification of the yarn mechanical properties using an inverse approach, based on tensile tests conducted on flax fabric reinforcement. The aim of this study is to develop a numerical method that allows to identify the statistical distributions of flax yarn properties based on tensile tests conducted on fabric specimens. The proposed strategy relies on two assumptions. On the one hand, fabric is constituted of several yarns acting like springs in parallel. On the other hand, yarns are considered as brittle-elastic materials. Hence, a yarn breaks when the load reaches its failure strength, leading to a loading redistribution to the intact yarns. A comparison of the numerical and experimental results of flax fabric tensile behavior, and of the flax property statistical distributions allows to confirm the performance of this strategy. The results show that the flax fabric tensile behavior is correctly described by the proposed modeling strategy. The average and the standard deviation of the Young's modulus, the tensile strength and the diameter of flax yarns identified from fabric tensile tests via inverse approach are close to those obtained experimentally on individual yarns. Indeed, the measured average diameter of unitary yarns are 244.4 ± 19.2 μm and the fitted one is 2474.8 ± 17.4 μm, the fitting failure strength 292.3 ± 33.4 MPa are close to the experimental 271.2 ± 47.5 MPa. The identified Young’s modulus is 9.4 ± 0.9 GPa is lower than the experimental 10.8 ± 1.3 GPa

International audience; A both multiscale and multi-techniques approach was developed to characterize the thermal aging in air at 70, 90, 100 and 120 °C of High Tenacity Polyvinyl Alcohol (HT-PVAl) yarns, and to elucidate the consequences of thermal aging on the chemical structure, crystalline morphology and several physico-chemical and mechanical properties of practical interest. First of all, FTIR and UV–Vis spectrometries showed that the main degradation products are isolated (1656 cm−1) and conjugated (1592 cm−1) carbon-carbon double bonds, and a large variety of carbonyl products such as: esters (1757 cm−1), aldehydes (1737 cm−1), carboxylic acids (1720 cm−1), ketones (1707 cm−1), but also polyenones (1630 cm−1). Possible mechanistic schemes were then proposed to explain the formation of all these different degradation products. Moreover, no change in the physico-chemical properties of the amorphous phase was detected by modulated differential scanning calorimetry and dynamic vapor sorption. In contrast, the decrease in both melting temperature and crystallinity ratio with exposure time clearly indicates a “nibbling” of the crystalline phase during thermal aging, thus highlighting a chemical attack preferentially localized at the amorphous/crystal interface for this complex anisotropic material. This heterogeneous degradation is responsible for the loss of fracture properties in tension of HT-PVAl yarns. Fairly simple relationships between the structural variables determined at the different scales of analysis were established. As an example, a linear correlation was found between the changes in fracture properties and the changes in crystalline morphology.

Nonconductive commercial viscose yarns have been coated with a commercial conducting poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) layer providing electrical conductivity which allowed a second coating of the electroactive conducting polymer polypyrrole through electropolymerization to develop textile yarns actuators. To simplify the PEDOT coating process and at the same time make this process more suitable for application in industry, a new coating method is developed and the properties of the PEDOT-PSS conducting layer is optimized, paying attention on its effect on the actuation performance. The effect of the concentration of an additive such as dimethylsulfoxide (DMSO) on actuation, and of PEDOT:PSS layers, is investigated. Results show that on improving this conducting layer, better performance than previously developed yarn-actuators is obtained, with strains up to 0.6%. This study provides a simple and efficient fabrication method toward soft, textile-based actuators for wearables and assistive devices with improved features. Funding agencies: The authors acknowledge the Erling-Persson Family Foundation,Promobilia Foundation (F17603), Union’s Horizon 2020 research andinnovation program under grant agreement no. 825232 “WEAFING”for their nancial support. E.W.H.J. acknowledges nancial support fromthe Swedish Government Strategic Research Area in Materials Science onFunctional Materials at Linköping University (Faculty Grant SFO Mat LiUNo. 2009 00971). F.E-T. acknowledges Universidad Tecnica de Ambato(UTA-FCIAL-UODIDE-2018-0047-M) for the financial support.

Electrical conductors based on carbons have recently attracted a growing interest due to the prospect of replacing metals. Electrical conductors without metals could represent not only an alternative for traditional wiring, but also a step forward in the progress and advancing of technology. This result can be achieved by combining high electrical conductivity with other properties, that are dexterity, light weight, environmental stability, high strength and flexibility. As the best mechanical properties, high electrical/thermal conductivity of the assembled fibers are all generally associated with low concentration of defects in the fiber backbone and in the individual carbon “building blocks”, a special attention is paid to an empirical relationship between morphology/structure/composition and the electrical properties. In this review, starting from the beginning, from the late 19th century, when the carbon filaments became the lights for urban streets, some of the recent developments in the field of “all-carbon” electrical conductors are discussed. Such conductors can be obtained by assembling nanoscale carbons (i.e., carbon nanotubes, graphene) into macroscopic fibers, yarns and ropes (hereafter fibers). In this perspective, the role played by the chemistry in particular by means of the molecular-level control and doping, is emphasized. This contribution elucidates most recent results in the field, and envisages new potential applications.

[ES] El objetivo principal del proyecto es estudiar la variación de propiedades físicas y conductoras que sufren tejidos de punto y calada una vez han sido insertados hilos de monofilamento/multifilamento conductivos mediante bordado. Para ello se estudiarán distintos sustratos textiles de diversas estructuras (estructuras de punto y calada) y gramaje, hilos conductores de distintas características, así como formas de bordado (lineal o zigzag). Todas las muestras obtenidas serán caracterizadas con tal de definir la modificación de propiedades tales como rigidez a la flexión, capacidad de desarrugado y conductividad., [EN] The main objective of the project is to study the alteration in physical and conductive properties that knitted and woven fabrics undergo once conductive monofilament/multifilament threads have been inserted by means of embroidering. To achive this, different textile substrates with different structures (knitted and woven structures) and weights, conductive yarns with different characteristics will be studied. All the samples obtained will be characterized in order to define the alteration of properties such as bending rigidity, surface roughness and tensile strength.

In this study, it was aimed to develop electrically and thermal conductive textiles surfaces. Pretreated polyester fabrics were coated with nano graphene powders at different concentration rates (50, 100, and 200 g/kg) by knife over roll technique. Electrical resistivity, thermal conductivity, thickness and mass per unit area measurements, bending rigidity, and abrasion resistance tests of coated fabrics were performed. Surface resistivity measurements of coated fabrics were made according to ASTM D 257 standard with Keithley 8009 Resistivity Test Fixture. Surface electrical resistivity values of coated fabrics decreased with increasing concentration rates. Of note, 2.53 x 10(4) omega/sq surface resistivity value was obtained at 200 g/kg graphene concentration rate. Thermal conductivity measurements of coated fabrics were made according to JIS R 2618 standard with Quick Thermal Conductivity Meter (QTM-710). Thermal conductivity property of fabrics improved depending on graphene concentration. The highest thermal conductivity value (0.4243 W/mK) was obtained at 200 g/kg graphene concentration rate. One of the most important results of the study was that a maximum weight loss of 0.40% was observed in the abrasion resistance test even after 100 000 cycles.

A lot of time is spent on detailed investigations of relaxation processes - from one second to a few days or weeks, and in some cases even more. Different relaxation processes inside the yarns are investigated extensively, however, within a short period of time in comparison, therefore, the behaviour of the product during long-lasting workloads cannot be predicted with reference to them. The aim of the dissertation - to create a new method for predicting long-lasting stress relaxation of yarns under short-lasting empirical investigations of stress relaxation. While carrying out the investigation, a method of predicting stress was created according to the break point observed during relaxation. It was found that this break point is common to all the investigated yarns of different constructions and origins, and while having different deformation values. Therefore, such a method can also be applied to other yarns that were not examined in this work. As the experimental investigations of stress relaxation can only be carried out up to a maximum of 1 000 seconds using the created method, the output data can be used to predict the relaxation process for a period of several days. The suggested method allows users to significantly decrease empirical investigations and can assess the relaxation process of the product quite fast, within an hour, in addition to calculating its behaviour for a long period of several days and additionally assist in making a decision about the suitability of the product and/or the values of the load with which the product can be operated., Išsamiems relaksacijos procesų tyrimams tenka sugaišti kelias dienas, savaites ar net dar ilgesnį laiko intervalą. Siūluose vykstantys skirtingi relaksaciniai procesai yra tirti gana nuodugniai, tačiau palyginti trumpą laikotarpį, todėl pagal juos negalima prognozuoti tekstilės gaminio elgsenos ilgalaikių apkrovų metu. Disertacijos tikslas – sukurti naują siūlų įrąžos ilgalaikės relaksacijos prognozavimo metodą pagal trumpalaikius įrąžos relaksacijos empirinius tyrimus. Įvairūs mokslininkai pastebėjo, jog įrąžos relaksacijos greitis relaksacijos metu yra nepastovus, t. y. po tam tikro laiko greitis mažėja. Šis momentas vadinamas relaksacijos lūžio tašku. Darbe sukurtas įrąžos prognozavimo metodas pagal relaksacijos proceso metu stebimą lūžio tašką. Nustatyta, kad lūžio taškas būdingas visiems tirtiems skirtingų konstrukcijų ir kilmės siūlams bei esant skirtingoms deformacijos vertėms. Todėl toks metodas gali būti taikomas ir kitiems, šiame darbe netirtiems, siūlams. Kadangi pagal sukurtą metodą eksperimentiniai įrąžos relaksacijos tyrimai gali būti atliekami tik iki 1000 sekundžių, o relaksacinė eiga pagal jį gali būti prognozuojama kelių dienų laikotarpiui, pasiūlytas metodas leidžia reikšmingai sumažinti empirinius tyrimus ir gana greitai, per valandą, nustatyti gaminio relaksacinę eigą, apskaičiuoti jo elgseną ilgam, kelių dienų, laikotarpiui ir priimti sprendimą dėl gaminio tinkamumo ir/arba vartojamųjų apkrovų verčių, kuriomis gaminys gali būti eksploatuojamas.

Novel, high-performance silver coated polyamide, Ag/PA66, nonwoven fabrics with a density of only 0.04 g/cm(3) have been developed using staple fibres of 19 (3.3 dtex) and 27 (6.7 dtex) mu m diameter. The obtained nonwoven fabrics with an Ag loading of 12-18 wt% exhibited excellent weight-normalised specific electromagnetic shielding effectiveness of over 1200 dB/(g/cm(3)) in the 0.015-3 GHz range, which is among the highest reported till date. Moreover, the applied microwave was verified to be absorbed rather than being reflected back making the fabrics highly suitable for shielding applications. It was also observed that nonwoven fabrics made from finer 3.3 dtex Ag/PA66 fibres have higher reflection and lower absorption values than their thicker (6.7 dtex) counterparts. Additionally, we have also explored the use of these nonwoven Ag/PA66 fabrics for personal thermal management via Joule heating with samples showing rapid heating response (up to 0.2 degrees C/sec) and long-term stability measured over 10,000 seconds. The needle-punched Ag/PA66 nonwoven fabrics, in spite of their low density of the order of 0.04 g/cm(2), exhibited high EMSE values of nearly 69-80 dB, leading to excellent weight-normalised specific electromagnetic shielding effectiveness of over 1200 dB/(g/cm(3)) in the 0.015-3 GHz range. The production of Ag/PA66 needle punched nonwoven fabrics thus offers a facile route to develop multifunctional fabrics for EMI shielding as well as personal thermal management applications.

The purpose of the study is to assess the irregularity elongation of wool yarn in a mixture with silk with the smoothness and torque of 470 Nm 34/1 twists / m, for knitted products. The study was conducted on two groups of yarns, batch 1 came from South Africa, and batch 2 from Asia, which was painted. In both groups there was 75% wool yarn and 25% silk. The measurements were carried out using the USTER® TENSOJET 4 machine, the analysis being performed on ten samples from each batch of yarns. During the mechanical processing and also during the use of textiles, the yarns are solicited by tensile forces, but most often by forces inferior to tearing forces. To highlight the behavior of yarns during strains to smaller stresses than those causing tearing itself, we must examine the stress-elongation diagrams and the irregularity regarding stress (tearing load and elongation to tearing). These stress characteristics have a major influence on deformability characteristics, dimensional stability, knitted products for which these yarns are intended. Thus it was found that the yarns from Asia, have a higher quality from the point of view of the tension proprieties having a lower irregularity defect from this point of view, contributing to obtaining a higher quality of the knitted product with a better dimensional stability than the products obtained from South Africa.

The electromagnetic shielding effectiveness (EMSE) of needle punched, nonwoven fabrics produced using staple stainless steel and carbon fibres was investigated. Utilising carding and large scale industrial type needle punching machines, webs of staple stainless steel and carbon fibres were produced, which were subsequently bonded on the needle punching machine at approximately 132 punches/cm(2) and 13.5 mm needle penetration depth. The effect of varying the carbon fibre content was studied by varying the blend ratio of stainless steel and carbon fibres between 5-20%. EMSE measurements of as-produced needle punched nonwoven fabrics were carried out using the coaxial transmission line method (ASTM D4935-10) in the frequency range of 15-3000 MHz. Within the range, the EMSE values were enhanced from 22.3 dB (95/5, stainless steel/carbon) to 44.7 dB (80/20, stainless steel/carbon), which was attributed to the enhanced conductivity of the fabrics. In fact, the surface resistivity of the samples decreased from 5.80E + 3 Omega to 2.43E + 2 Omega, enhanced for 95: 5 and 80: 20 stainless steel/carbon blends.

This research presents the investigation of the influence of flame retardant concentration on the flammability properties of various kinds of cellulose fibres. The industrial flame retardant Aflamit®KWB (Thor GmbH, Germany) reagent and the yarns of three kinds of cellulose fibres (cotton, flax and peat) of linear density 200±10 tex have been chosen for investigation. The various concentration of flame retardant reagent was used for all kinds of yarns. The basic concentration of Aflamit®KWB was chosen according to the Thor GmbH standard recommended for the application. Also, the concentration was used 2, 3, 4, 6, 8 and 16 times lower than the basic concentration. The horizontal tests of yarn’s flammability (time of burning) and vertical tests of flame spread (speed of spread) were carried out. The results obtained have been compared with the results of flame retardant metaaramide yarns Nomex (DuPont, USA) and with results obtained earlier by co-author of present investigations [1, 2]. The investigation shows that even when the concentration is 4 times lower than basic, it provides similar flammability properties to the analogous properties of Nomex yarns. The differences between properties of various kinds of cellulose yarns were investigated as well. The best results of flammability properties have been obtained for cotton yarns and the lowest - for flax yarns. The reason for these differences can be explained by composition of various kinds of cellulose fibres. The influence of concentration of flame retardant reagent on the strength of yarns was investigated too. The research shows, that oncentration has a negative influence on the strength of yarns – when concentration increases the strength decreases. The results of investigation show that concentration of flame retardant reagent can be used in much lower levels than is recommended by the producer. Also the lower level of concentration supports the higher strength of yarns. The lower concentration can be recommended for textile goods which are not necessary to wash.

With industrial progress, the advancements in garment manufacturing have evolved from cut & sew to complete garment knitting, which produces one entire garment without sewing or linking process. Seamless knitting technology is similar to sock manufacture, the specialized circular knitting machines producing 3 dimensional garments with no side seams, with the waistband integrated with body of the garment and with knitted washing instructions and logos. The paper starts by presenting the main advantages of seamless garments but also some limitations because the technology. Because for a seamless garment, which is realized as a knitted tub, is very important to ensure the required final chest size, it was presented the main components involved: the knitting machine, the garment design and the yarns used. The knitting machines, beside the values of diameters and gauges with a great impact on the chest size, are characterized by a very innovative and complex construction. The design of a seamless garment is fundamental different compared to garments produced on a traditional way because the designer must to work backwards from a finished garment to create the knitting programme that will ultimately give the correct finished size. On the end of the paper it was presented some of the applications of the seamless products that cover intimate apparel and other bodywear, outwear, activewear and functional sportswear, upholstery, industrial, automotive and medical textiles.

From the technological point of view it is necessary that the phase of warping to be done two or three multiple warp, which results in two or three rolls of the warp final will meet only the warping. To achieve longitudinal striped fabric spinning machines is necessary to have all tensioning mechanism dispensing rolls which requires their special construction. The homogeneity of the fabric from the point of view of the warp yarns tension must be ensured by synchronizing operation of the tensioning two cutting mechanisms of the two reels on which the wires are wound with a degree of waving and thus the fuel consumption at the different weaving. It is recommended that the design be adopted average float bonds, such that the wires can be wrapped around more than two final reels. In terms of manufacturing technology with longitudinal stripes fabrics have a more complicated and expensive technology to cross-striped fabrics for the manufacture of which technology is simplified. Cross-striped fabrics containing groups of warp threads those linked to floating average is materially different. Due to this degree of crimping of wires in the stripes with different bonds makes their contract to be different, having a direct influence on the wires consumption. The different contraction of wire weaving makes warp yarn length, contained in a linked reports are so different that it requires winding wires with different bonds also differing on the final rolls.

The comfort is undoubtedly the most important human attribute depends upon the moisture transport which in turn depends on the moisture transport behavior of the knitted fabric. Moisture transport is the transfer of liquid water capillary interstices of the yarns and depends on the wettability of fiber surfaces, as well as the structure of the yarn and fabric. Because of its good water absorption property, cotton is often used for next-to-skin wear such as t-shirts, underwear, socks. All these are known as ``moisture management`` which means the ability of a textile fabric to transport moisture away from the skin to the garment’s outer surface in multi-dimensions and it is one of the key performance criteria in today’s apparel industry since it has a significant effect on the human perception of moisture sensations. In order to study, plated knitted fabric for socks were knitted as plated single jersey in the same production conditions, from different types of yarns, produced in different yarn counts (Ne 20, Ne 24, Ne 30) and different raw material. (cotton, bamboo, soybean, polyester, viscose). Were chose two different density on circular knitting machine. The liquid moisture management of the samples was measured in order to determinate moisture transport index. Was study also the influence of raw material and fabric structure related to the moisture transport index. According to the obtained results, it was found that some of the knitted fabrics used in this study have goodmoisture management capability.

This paper reports an overview of advanced auxetic fibrous structures and composites for various industrial applications. Most recent developments in the area of auxetic fibres, yarns, textile structures and composites are reviewed. Innovations in terms of materials, design and structures, processing technologies and innovative applications have been critically reviewed., This work is supported by Portuguese National Funding, through FCT - Fundação para a Ciência e a Tecnologia, through the project grant, PTDC/CTM-POL/5814/2014., info:eu-repo/semantics/publishedVersion

In the manufacture of yarn, predicting the effect of changing production conditions is vital to reducing defects in the end product. This study compares, for the first time, non-linear regression and artificial neural network (ANN) models in predicting 10 yarn properties shaped by the influence of winding speed, quenching air temperature and/or quenching air speed during production. A multilayer perceptron ANN model was created by training 81 patterns using the Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm. The hyperbolic tangent, or TanH, activation function and logistic activation functions were used for the hidden and output layers respectively. Results showed that the ANN approach exhibited a greater prediction capability over the nonlinear regression method. ANN simultaneously predicted all of the 10 final properties of a yarn; tensile strength, tensile strain, draw force, crystallinity ratio, dye uptake based on the colour strengths (K/S), brightness, boiling shrinkage and yarn evenness, more accurately than the non-linear regression model (R2=0.97 vs. R2=0.92). These results lend support to the idea that the ANN analysis combined with optimization can be used successfully to prevent production defects by fine tuning the production environment.

Tensile property of textile yarn is a prime important parameter in establish the suitability for any particular application. Breaking strength, elongation, elastic modulus, abrasion resistence etc. are some important factors which will represent the performance of the yarn. It is therefore of utmost importance to determine this characteristic accurately. Raw material characteristics influence properties of the knitted products. The yarns are subjected to mechanical stress during knitting and while wearing the products. The most common types of force applied to knitted fabrics is traction, which usually does not exceed 25 to 30% of breaking strength. In some cases the tensile forces are higher and are producing remanent deformation and damages. On getting dressed, the product is stretched out with a force bigger than during the wearing.Because socks are subjected to tensile forces both in the dry and wet state, we have studied the tensile strength and the breaking elongation for different types of yarn used in knitting these products. Tests were made in dry and wet state using SR EN ISO 2062:2000 Textiles - Yarns from packages- Determination of single-end breaking force and breaking elongation, using Titan2 device. The testing results for tensile strength and breaking elongation are presented in graphics and analysed.

Magistrinio projekto tikslas - nustatyti technologinių sąlygų įtaką skersinių mezginių, skirtų viršutinių drabužių asortimentui, struktūrinėms ir mechaninėms savybėms. Magistrinio projekto eksperimentiniams tyrimams atlikti buvo pasirinkti trijų skirtingų pluoštinių sudėčių verpalai. Tai 100 % vilnoniai verpalai, mišriapluoščiai 50/50 % vilna/PAN verpalai ir 100 % PAN (akrilnitriliniai) verpalai. Tyrimams reikalingi bandomieji mezginiai buvo numegzti lygiuoju skersiniu pynimu 10E klasės plokščiąja skersinio mezgimo mašina UAB ,,Garlita“. Bandinių mezgimas buvo organizuotas keliais etapais. Iš visų trijų pluoštinių sudėčių verpalų buvo numegztos penkios mezginių partijos. Bandomieji mezginiai buvo numegzti iš nekondicionuotų verpalų ir 1, 2, 5, 24 valandas kondicinėmis sąlygomis išlaikytų verpalų. Tyrimo metu buvo nustatyti vertikalusis ir horizontalusis megztų bandinių tankumo koeficientai, kurie buvo matuojami šešiais etapais: iš karto po mezgimo bei bandiniui išbuvus 1, 2, 5, 10 ir 24 valandas kondicinėse sąlygose. Nustačius vertikalųjį ir horizontalųjį megztų bandinių tankumus buvo apskaičiuotos mezginių kilpos aukščio ir kilpos žingsnio vertės. Tyrimo metu nustatyta technologinių sąlygų įtaka mezginio matmenims. Siūlų kondicionavimo ir mezginių relaksavimo po mezgimo įtaka mezginio detalės matmenims vertikalia ir horizontalia kryptimis buvo nustatoma įvertinant kilpos geometrijos pokyčius. Taip pat visų trijų pluoštinių sudėčių verpalams ir bandomiesiems mezginiams buvo atliktas deformacinių ir stipruminių savybių tyrimas. Atlikus tyrimus nustatyta, kad didėjant siūlų kondicionavimo trukmei, kilpos plotis nuosekliai mažėja ir horizontalusis kilpų tankumas nuosekliai didėja. Tyrimai parodė, kad megztos detalės matmenims turi įtakos tiek verpalų kondicionavimo, tiek mezginio relaksavimo trukmė. Taip pat nustatyta, kad verpalų relaksacija kondicinėmis sąlygomis mezginių stiprumui įtakos neturi. Tačiau pastebėta ženkli įtaka trūkimo ištįsai., The aim of the research project was to determine the influence of the technological conditions on to the structural and mechanical properties of plain single jersey-knitted fabrics intended for outerwear range. Three different type yarns with different fibre compositions have been selected for the experimental investigations: 100% woollen yarns, 50/50 % wool/PAN blended yarns and 100% PAN (acrylic) yarns. The samples of plain single jersey-knitted fabrics, used for investigations, have been knitted in UAB “Garlita” using a 10E gauge flat double needle bed weft knitting machine. The knitting of the samples was organized in several stages. Five parties of knitted fabrics have been knitted using all three different yarn compositions. The fabrics were knitted of unconditioned yarns and of yarns, conditioned in standard atmosphere conditions for 1, 2, 5, and 24 hours. The course and wale density coefficients of knitted fabrics were determined. They were measured in 6 stages – immediately after knitting and after fabrics were conditioned for 1, 2, 5, 10, 24 hours in standard atmosphere conditions. After determining the course and wale densities, the course spacing and the wale spacing values of knitted fabrics were calculated. The influence of the technological properties on to the knitted fabric dimensions was also found in the research. The influence of yarn conditioning and relaxation after the knitting to the knitted fabric dimensions in both horizontal and vertical directions was determined by evaluating the geometrical changes of the stitches. Also, the deformation and strength properties for all three different types of yarns and all knitted fabrics were measured during the tensile test. It was determined that increasing of conditioning duration leads to consistent decrease of the wale spacing and to the consistent increase of course density. Also, it was found that relaxation duration of both the yarn and the fabric have significant influence on to the final dimensions of the fabric. It was also found that relaxation of the yarns in standard atmosphere conditions has no influence to the knitted fabric strength properties. However, it has significant influence on to the elongation values.

In this paper, the effect of weaving machine settings on weavability limits of air-jet looms was investigated by weaving plain weave fabrics with polyester warp and weft yarns. For this purpose, firstly, weavability limits were determined for 16.7 tex weft by setting back-rest height, total warp tension, frontshed angle and shed closing time at different levels without changing the properties of warp. For each machine setting, weft density was increased gradually until reaching the weavable limit. During the experiments, weaving continuity, unfavorable effects interrupting this continuity, negative changes on fabric and yarns were observed. In the mean time, the warp yarn tension and cloth-fell distance were measured. Later, the weaving with 7.8 and 33.3 tex wefts was carried out at the settings required to produce a weave at the maximum weft density for 16.7 tex weft. The maximum weavable weft densities were determined for these two weft yarns. Finally, the obtained maximum weft densities and cover factors with three different weft yarns were compared with the results obtained from theoretical equations of Pierce, Love and Brierley. It was found that the warp tension had the most significant effect on the weavability limits. Changing shed adjustment from the zero level of the back rest to higher values, increased the weavability limit slightly, but increasing the shed asymmetry further did not have a significant effect on the weavability limit. The shed closing time had some effect on the limit. But this was less than the effect of the warp tension. Changing the front shed angle did not have any effect on weavability limits. © 2011, SAGE Publications. All rights reserved.

This study was performed in order to investigate the effects of tandem and conventional vacuum steaming on the physical properties of 100% cotton and 100% viscose yarns. The yarns with different twisting coefficients and numbers were twisted and exposed to tandem and conventional vacuum steaming at different temperatures. Tenacity, unevenness, hairiness, twist liveliness, package hardness values, and spirality of knitted fabrics produced from these yarns were measured before and after vacuum steaming. The results obtained were assessed by means of COSTAT statistical analysis program. Variation analysis and SNK test were carried out at 5% (0.05) level of significance. The findings of this study indicate that the effects of vacuum steaming methods on the tenacity, unevenness, hairiness, twist liveliness and package hardness values of yarns are statistically significant. Although the effects of tandem vacuum steaming vary depending on the temperature applied and the raw material used, decreases are observed in unevenness, hairiness, twist liveliness and package hardness values of yarns. Apolteks Textil San. Tic. A.Ş Epiriler Textil San. Tic. A.Ş

In this paper, a line-laser-based yarn break sensor is proposed. In the proposed sensor, yarns are illuminated by a line laser placed on one side of the yarn plane. A screen is placed on the other side and the image formed on the screen is detected by a camera. The total number of yarns is compared with the total number of shadows formed by the yarns or the total number of light spots formed due to the distances between yarns. If the total number of yarns to be detected is greater than the total number of shadows or light spots formed due to the distances between the yarns, the sensor warns of breaking. In the proposed method, evaluation is made using only light spots or shadows formed by the yarns. Consequently, the yarn type, structure, color, or dimensions do not affect the results. Design principles of the line-laser-based yarn break sensor, which consists of a screen and a Charged Coupled Device (CCD) camera, are presented. The screen displays the shadows formed by the yarns and the light spots formed due to the distances between them. The CCD camera detects the image on the screen. Formation of the shadows by the yarns is explained and an analytical formula that expresses the dimensions of the shadows is obtained. The detection area of the sensor is expressed relative to the total number of yarns, yarn thickness, and distances between the yarns. Line laser radiation angle and light spot intensity equations are obtained relative to the width of the detection area and the height of the line laser placement. The screen length is obtained relative to the number of yarns and the placement of the laser, the yarn plane, and the screen. Different placement situations of the line laser (transmitter), the screen, and the CCD camera (receiver) relative to the yarn plane are discussed. An experimental setup is developed to test the system. The image formed on the screen is studied.

Alternating current–driven electroluminescent devices on polyester fabrics were realized using a combination of coating and printing. The PEDOT:PSS front electrode was coated onto the fabric using knife coating. All other layers were digitally printed using a specially modified three-dimensional printer and three-dimensional printing software. Slicing parameters (line distance, printing speed, printing pattern) as well as other hardware parameters and ink viscosity were evaluated for each ink to obtain a good print. Final results show a complex interaction of all investigated parameters. Fully digitally printed electroluminescent devices show a luminescence of 44 lx, but combinations of digital printing and knife coating show a much higher luminescence of up to 128 lx for samples with an even smaller luminous layer thickness.

This paper is part of a research agreement between "Aurel Vlaicu" University and The NationalResearch - Development Institute for Textile and Leather, Bucharest, about the relationship of interdependencebetween the yarns' characteristics and fabric's characteristics for the installation of ventilation and heating pipesof the military helicopter[5]. Fabrics for strategic areas must have certain characteristics such resistance at hightemperatures, breaking and tearing strength, shock resistance and chemicals' resistance.This paper presents a concrete case of mathematical modelling of the yarns characteristics and the fabricabrasion resistance for ventilation and heating ducts of a military helicopter.

Producing high quality knitted fabrics, as well as the efficient use of raw material, requires knowing the major yarn proprieties in correlation with the product destination. The criteria used to establish the priority characteristics for a certain destination leads to narrowing the yarn pallet utilized for a particular domain.This paper presents the results of the quality evaluation of several OE cotton yarns, witch were processed on large diameter circular knitting machines.

This paper is part of a research agreement between "Aurel Vlaicu" University and The National Research - Development Institute for Textile and Leather, Bucharest, about the relationship of interdependence between the yarns' characteristics and fabric's characteristics for the installation of ventilation and heating pipesof the military helicopter[5]. Fabrics for strategic areas must have certain characteristics such resistance at high temperatures, breaking and tearing strength, shock resistance and chemicals' resistance.This paper presents a concrete case of mathematical modelling of the yarns characteristics and the fabric abrasion resistance for ventilation and heating ducts of a military helicopter.

In this study, the effect of vacuum steaming temperature and time on the physical properties of polyamide (PA) 6 yarns has been investigated. Also, the effect of vacuum steaming temperature and time on twist liveliness and package hardness of PA 6 yarns has been studied and the results obtained have been evaluated using statistical methods. Further, the effect of vacuum steaming on dyeability properties of PA 6 yarns has been examined and the effect of vacuum steaming temperature and time on dye absorption properties of PA 6 yarns has been analyzed. As a result of this study, it has been seen that vacuum steaming temperature and time have significant effects on the tenacity properties, twist liveliness, package hardness, and dyeability properties of PA 6 yarns.

In this paper, current yarn break sensor systems are investigated and a line laser-based yarn break sensor is proposed. In this proposed sensor system, yarns aligned in the same plane are illuminated with a line light and the light spots on the yarns are detected with a CCD camera, total yarn number is compared with the number of the light spots formed by the line laser on yarns. If the number of the yarns used is greater than the number of the light spots, sensor warns the breaking. Design principles of the line laser-based yarn break sensor are presented. Detection area of the sensor related to the yarn number, yarn thickness and the distances between the yarns is obtained. Equations for calculating the line laser radiation angle and the light spot intensity related to the detection area width and the line laser placement height are obtained. Different placement situations of line laser (transmitter) and the CCD camera (receiver) related to the yarn plane are explained. An experimental setup is developed to test the system and the image of the light spots formed on yarns is obtained. Block diagram of the sensor is given and the operation principle is explained.

Cellulose nanofibrils (CNF) are promising bio-based materials for numerous applications, either as replacement of oil-based materials in existing products, potentially with added functionality, or in generating novel materials and products. VTT has been involved in CNF research since 2008, and has expertise related to their manufacturing, modification, characterization, safety and sustainability, rheology and processability, as well as to selected applications. Examples of applications which are considered very potential and strategically important for VTT include paper and board, films and CNF filaments and yarns. Recent developments in the production of cellulose nanofibrils at high consistency with an economically feasible manner have removed major challenges related to industrial production of CNFs.

Cellulose nanofibrils (CNF) are promising bio-based materials for numerous applications, either as replacement of oil-based materials in existing products, potentially with added functionality, or in generating novel materials and products. VTT has been involved in CNF research since 2008, and has expertise related to their manufacturing, modification, characterization, safety and sustainability, rheology and processability, as well as to selected applications. Examples of applications which are considered very potential and strategically important for VTT include paper and board, films and CNF filaments and yarns. Recent developments in the production of cellulose nanofibrils at high consistency with an economically feasible manner have removed major challenges related to industrial production of CNFs.

This paper describes the modelling of the structure and mechanical parameters of rope components made of natural fibers. Modern X-ray micro-tomography (Micro-CT) was employed to measure the parameters of the internal structure of the multi-component yarns making up rope and utilized as a basic model of twisted rope. The results allowed calculation of the tensions generated in the component yarns and detection of the unevenness of the filling of the component yarns by fibers, which was clearly visible in cross-section. The unevenness of twist measured as a function of distance from the center of the yarn was also detected. The unevenness of fiber distribution in the twisted element decreased its intensity, starting from the surface of the yarn and going deeper into the structure. Migration of the fibers in the frame of the circumference of the component yarns was associated with the mutual slide of single fibers.

In this paper, cocoon properties are examined, spectral characteristics and mathematical expressions that define cocoon shell's absorption and reflection of light in various wavelengths are obtained and given in graphical form. Finally, optoelectronic methods and systems that determine cocoon properties are designed and explained.

Transparent and flexible electrodes are widely used on a variety of substrates such as plastics and glass. Yet, to date, transparent electrodes on a textile substrate have not been explored. The exceptional electrical, mechanical and optical properties of monolayer graphene make it highly attractive as a transparent electrode for applications in wearable electronics. Here, we report the transfer of monolayer graphene, grown by chemical vapor deposition on copper foil, to fibers commonly used by the textile industry. The graphene-coated fibers have a sheet resistance as low as ~1 kΩ per square, an equivalent value to the one obtained by the same transfer process onto a Si substrate, with a reduction of only 2.3 per cent in optical transparency while keeping high stability under mechanical stress. With this approach, we successfully achieved the first example of a textile electrode, flexible and truly embedded in a yarn.