This article reports the successful manufacturing of hybrid yarns from virgin staple CF (40 or 60 mm) or recycled staple CF (rCF) by mixing with polyamide 6 (PA 6) fibers of defined length. The hybrid yarns are produced using an optimized process route of carding, drawing, and flyer machine. Furthermore, the influence of CF length, CF type (i.e. virgin or rCF), CF volume content, and twist of the yarn are also investigated regarding the tensile properties of unidirectionally laid (UD) thermoplastic composites. The results show that CF length, yarn twist, and CF content of composites play a big role on the tensile properties of thermoplastic composites. From the comparison of tensile strength of UD composites produced from 40 and 60mm virgin staple CF, it can be seen that the increase of yarn twist decreases the tensile strength. However, the effect of twist on the tensile properties of UD composites manufactured from 40mm virgin staple CF is insignificant. The tensile strength of UD thermoplastic composites manufactured from the hybrid yarn with 40 and 60mm virgin staple CF and rCF is found to be 771 ± 100, 838 ± β1, and 801 ± 53.4 MPa, respectively, in the case of 87 T/m containing 50 volume% CF.

The optimization of the spinning process and adjustment of the machine settings involve “Trial and Error” method resulting in the wasting of production time and material. This situation becomes worse in the spinning mills where the speed and material changes are frequent. This research includes the use of artificial neural networks to provide the thinking ability to the spinning machines to improve the yarn spinning process. Draw frame, being the central part of the spinning preparation chain and last machine to rectify the variations in the fed slivers is the main focus of the research work. Artificial neural network have been applied to the leveling action point at auto-leveler draw frame and search range of leveling action point has been considerably reduced. Moreover, the sliver and yarn characteristics have been predicted on the basis of draw frame settings using the artificial neural networks. The results of present research work can help the spinning industry in the direction of limiting of “Trial and Error” method, reduction of waste and cutting down the time losses associated with the optimizing of machines. As a vision for the future research work the concept of intelligent spinning machines has also been proposed. / Die Optimierung des Spinnprozesses und die Maschineneinstellung erfolgen häufig mittels „Trial und Error“-Methoden, die mit einem hohen Aufwand an Produktionszeit und Material einhergehen. Diese Situation ist für Spinnereien, in denen häufige Wechsel des eingesetzten Materials oder der Produktionsgeschwindigkeit nötig sind, besonders ungünstig. Die vorliegende Arbeit zeigt das Potenzial Neuronaler Netze, um die Spinnmaschine zum „Denken“ zu befähigen und damit die Garnherstellung effektiver zu machen. Die Strecke ist der zentrale Teil der Spinnereivorbereitungskette und bietet die letzte Möglichkeit, Inhomogenitäten im Faserband zu beseitigen. Der Fokus der Arbeit richtet sich deshalb auf diese Maschine. Künstlich Neuronale Netze werden an der Strecke zur Bestimmung des Regeleinsatzpunktes genutzt, womit eine beträchtliche Reduzierung des Aufwands für die korrekte Festlegung des Regeleinsatzpunkts erreicht wird. Darüber hinaus können mit Hilfe der Neuronalen Netze die Band- und Garneigenschaften auf Basis der Streckeneinstellungen vorausbestimmt werden. Die Resultate der vorliegenden Arbeit machen „Trial und Error“-Methoden überflüssig, reduzieren den Ausschuss und verringern die Zeitverluste bei der Maschinenoptimierung. Als Zukunftsvision wird eine Konzeption für intelligente Spinnmaschinen vorgestellt.

3D textile performs offer a high potential to increase mechanical properties of composites and they can reduce the production steps and costs as well. The variety of woven structures is enormous. The algorithms based on the conventional weaving notation can only represent the possible woven structures in a limited way. Within the scope of this dissertation, a new weaving notation was developed in order to analyze the multilayer woven structures analytically. Technological solutions were developed in order to guarantee a reproducible preform production with commingled hybrid yarns. Terry weaving technique can be utilized to create vertical connections on carrier fabrics, which makes it suitable for the development of complex profiles. A double rapier weaving machine was modified with electronically controlled terry weaving and pneumatic warp yarn pull-back systems. Various spacer fabrics and 3D profiles were developed. A linear take-up system is developed to assure reproducible preform production with a minimum material damage. Integrated cutting and laying mechanisms on the take-up system provides a high level of automation.

This master thesis studies the recycling prospects of textiles. The textile industry contributes negatively to the global environmentthrough the release of greenhouse gases and consumption of resources. In order to achieve a circular textile industry, textiles must be recyclable by both chemical and mechanical means. Here, the focus is on mechanical extraction of staple fibres, particularly cotton, for reentry into yarn production. Experiments show that used, but undamaged, cotton sateen and cotton twill responds differently to abrasion with stochastic surfaces. Previous studies on the conventional shredding processes have shown positive impact from lubricants on extracted fibre lengths, by reducing inter-fibre friction. In the present study on abrasion, variables such as alignment of the weave pattern, lubrication and load are shown to have little to no impact on extracted fibre length, but notable effects on overall fibre quality. These analyses are supported by manual length assessment, electron micrographs and tensile tests using load cells. Furthermore, simple tests and observations on structured diamond surfaces constructed through chemical vapor deposition are promising for mechanical fibre release directly from a woven fabric. Suggestions are made on continued research in this field.

Denna rapport beskriver arbetet med att konstruera utrustning för att strimla, tvinna och fixera en flerskiktsfilm i form av reflextejp med avsikten att tillverka garn av den strimlade tejpen där garnet slutligen stickas och vävs till tyger. Avsikten är inte att utveckla reflexgarn eftersom existerande metoder finns för detta, utan att undersöka om garntillverkning från filmmaterial, eller i en förlängning, andra tvådimensionella material lämpar sig för garnproduktion. Om metoden går att utveckla till kostnadseffektiva, industriella processer kan den exempelvis användas för återvinning av textilier i steget innan konsumentnivå. Överproduktion och tyger med fabrikationsfel inom textilindustrin skulle hypotetiskt kunna strimlas till remsor som tvinnas till relativt grova garner i mekaniska processer. En fördel är att materialblandningar och tillsatta additiv som normaltsett försvårar återvinning inte behöver beaktas. Ett annat tänkbart användningsområde är att råvaror som inte är lämpliga till fibertillverkning kan användas förtextilproduktion. Cellulosabaserat material som används till papperstillverkning där papperet sedan strimlas och tvinnas till garner är ett relativt nytt exempel på garnproduktion från tvådimensionell struktur som just nu är under utveckling. De konstruktioner som tillverkades för strimling, tvinning och fixering fungerade för att producera garner som gick att virka, sticka och väva med. En avgörandefaktor för garnkvaliteten var vilken slags polymer som reflextejpens lim var uppbyggd av. Polyuretan visade sig ge det mest användbara garnet och drygt tvåhundrameter garn av detta material tillverkades under arbetet. De processer och metoder som utvecklats är att betrakta som initiala steg, men är uppskalningsbara till kontinuerliga tillverkningsmetoder i industriell produktion. / This report describes the work of designing equipment for shredding, twisting and heat fixate a multilayer film in the form of reflective tape. The intention is to produce yarn of the shredded and twisted tape, where the yarn is finally knitted and woven into fabrics. The intention is not to develop reflex yarns because existing methods exists for this, but to investigate whether yarn production from film materials, or in an extension, other two-dimensional materials are suitable for yarn production. For example, if the method can be developed into cost-effective industrial processes, it can be used for textile recycling in the pre-consumer stage. Overproduction in the textile industry and fabrics with defects could hypothetically be shredded into strips that are twisted into relatively coarse yarns in mechanical processes. One advantage is that material mixtures and additives which normally make recycling difficult need not be taken into account. Another conceivable area of application is that raw materials which are not suitable for fiber production can be used for textile production. Cellulose-based material used for paper where the paper is shredded and twisted into yarns is a relatively new example of yarn production from a two-dimensional structure that is currently under development. The constructions made for shredding, twisting and heat fixation worked to produce yarns that could be transformed into fabrics. A decisive factor for the yarn quality was the kind of polymer on which the tapes adhesive film was made from. Polyurethane was found to provide the most useful yarn and more than two hundred meters of yarn were made from this material during the work. The processes and methods that have been developed are considered initial steps, but are scalable to continuous manufacturing methods in industrial production.

The yarn tension and balloon form are the most important physical process parameters to characterize the dynamic yarn path in ring spinning. The present research work focuses on the in situ measurement of yarn tension in different regions of the yarn path in a developed turbo ring spinning tester with a friction-free superconducting magnetic bearing (SMB) twisting system and at an angular spindle speed of up to 50,000 rpm. The influence of different parameters, such as angular spindle speeds (15,000–50,000 rpm), yarn counts (15–40 tex) and balloon control ring (one or multiple), were evaluated to identify the influence of acting forces, for example, centrifugal forces. The effects of these process parameters were analyzed statistically using an analysis of variance. The yarn tension between the delivery rollers and the yarn guide was measured using a modified one-roller tensile yarn tension sensor. The yarn tension between the yarn guide and the SMB system was determined with an already existing optical approach at a higher angular spindle speed. As the highest yarn tension theoretically occurs between the SMB system and the cop, it was estimated in this region by measuring the coefficient of friction between the yarn and the yarn guide using the friction module of the constant tension tester equipment. The maximum balloon diameter was determined from the recorded balloon form between the yarn guide and the SMB system with respect to different angular spindle speeds. The results provide valuable information about the highest possible spinnable speed and enable a better understanding of the dynamic yarn path in the SMB spinning system. Keywords

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.

Composites have now revolutionized most industries, like aerospace, marine, electrical, transportation, and have proved to be a worthy alternative to other traditional materials. However for a further comprehensive usage, the tailorability of hybrid composites according to the specific application needs on a large-scale production basis is required. In this regard, one of the major fundamental research fields here involves a technology development based on the multiaxial warp-knitting technique for the production of bionic-inspired and application-specific textile preforms that are force compliant and exhibit multi-material design. This article presents a newly developed yarn (warp) path manipulation unit for multiaxial warp-knitting machines that enables a targeted production of customized textile preforms with the above characteristics. The technological development cycle and their experimental validation to demonstrate the feasibility of new technology through production of some patterns for different field of applications are then discussed.

Collagen fibres from reindeer tendons can be used to create threads. These threads have traditionally been used in Sápmi crafts. Due to the high cost of manual extraction, tendon-based threads have been replaced with cheaper synthetic threads. However environmental concerns have been raised within the Sápmi crafts communities regarding the synthetic threads. To mitigate the impacts of synthetic threads and to better utilize the reindeer after slaughter a more efficient fibre extraction process has been sought after. In this study two venues have been investigated, softening and retting. In this study softening will refer to the breaking of bonds through the use of a liquid. Retting will refer to a controlled degradation of a material through biological processes. Softening and retting aided mechanical extraction of collagen fibres. The softening, using water and in some cases polyethylene glycol, reduced entanglement and friction. The retting can be divided into short term retting and long-term retting, up to six weeks. Neither the short-term retting nor the long-term retting did facilitate the extraction significantly compared to a simpler softening treatment. Softening on the other hand made extraction easier. A 70 hour softening with water at room temperature had the largest impact. The extraction became slightly easier when the samples were further softened with polyethylene glycol. This was compared to a reference sample where water was used for further softening. Mechanical fibre extraction methods were also evaluated. The softened tendon samples were calendered between two rollers at 1.2 bar and 5.0 bar. The samples using the higher pressure were easier to separate. The samples were then manually torn apart into fine fibre bundles. Many of the manual methods used can be automated but they would need specialized equipment. The mechanically extracted fibres were then spun into yarns through hand spinning with moistened fingers. The tensile properties of the fibres and the yarns were determined. The fibres and the yarns were also evaluated through light microscopy. Both the yarns and fibres showed a high degree of variation in the tensile tests. The use of manual methods likely contributed to the high variation. The yarns slipped which caused a lower tenacity compared to the fibres. The mean fibre tenacities were between 17-20 cN/tex, depending on factor. Neither of the factors were significantly different. The elasticity of the fibres varied to a large extent. The fibres exhibited an almost fully elastic deformation until break. The fibres were white to cream and slightly translucent when viewed in a light microscope. The yarns were uneven and glossy.

The degradation of wool keratin under conditions relevant to those of wool dyeing was investigated using the techniques of gel permeation chromatography (GPC), ion exchange gel chromatography, and amino acid analysis. Physical testing of the treated and untreated wool was also carried out to determine the physical changes occurring, parameters used being percentage elongation at the break, and the breaking strain of the fibre. Samples of wool keratin were immersed in various aqueous solutions at 1000C for 24 hours and the filtered, aqueous, oxidised extracts were analysed* The solutions used varied only in the dye, or dye intermediate present in the treatment solution. All treatment baths contained 10% owf 1.02 x 10 -2 MSulphuric VI acid; 10%owf 7.04x 10 -3 MSodium sulphate VI ; A 100 :1 liquor ratio was used in each case. Some of the dye intermediates showed a marked catalytic effect, particularly in their effect on breaking strain, a decrease of 40% in some cases. The GPC profiles of the extracted proteins were examined in detail and compared against previous workers' results. An explanation of the behaviour of the dyes and intermediates was proposed. The amino acid composition data of the extracted and fractionated proteins were compared against various morphological components extracted by other workers, as was the total gelatin obtained from each treatment. / Science Research Council