Demet Yilmaz

A comparison of compact-jet, compact, and conventional ring-spun yarns

This study compared the characteristic properties of the yarns produced on three different yarn spinning systems with the same material. These spinning systems are conventional ring, compact, and compact-jet. Compact-jet is a proper combination of compact and jetring-spinning systems and therefore it is less known. On the other hand, conventional ring and compact spinning systems are well known in the spinning field. When the compact-jet spinning system was designed, it was aimed to gather the advantages of the jetring and compact spinning systems. Therefore, an air nozzle was placed between the exit of the RoCoS compact unit and the yarn guide of the spinning system. At the end of the study, it was determined that the compact-jet yarn properties are different from that of the conventional ring and compact yarns. The compact-jet spinning system is mainly effective on yarn hairiness and compact-jet yarn is superior compared with other yarns.

Improvement in yarn hairiness by the siro-jet spinning method

Hairiness affects the post-spinning processes and fabric appearance. In order to reduce the yarn hairiness, the present work attempted to design and develop an air nozzle that can be easily attached on to the sirospun spinning system. The system, based on a nozzle attachment to the sirospun spinning system, is named the siro-jet. In our previous studies, the nozzle was used in ring and compact spinning processes and the changes in yarn properties were analyzed. In this study, various nozzles having different injector angles, main hole diameters, injector diameters, number of injectors, nozzle shapes and injector positions were used and siro-jet yarns were produced at different air pressure levels. At the end of the experiments, it was determined that there is an optimum value for each nozzle parameter, and that the number of injectors and injector position play the most important roles in reducing yarn hairiness, whereas nozzle shape shows the weakest effect. On the other hand, the findings showed that it is possible to get lower hairiness values by different modifications on the same nozzle design. Considering the hairiness results, a constant was defined indicating the relationship between nozzle structural parameters and hairiness of the yarns to ease the nozzle design efforts. Depending on nozzle type, the siro-jet spinning system truly improves the yarn hairiness by 40–75%. In the literature, many researchers used an air nozzle in the spinning and also the winding processes. However, the combination of the air nozzle and sirospun spinning system in this manner is still not a common application.

Comparison of Selected Properties of Eco- Friendly Soybean and Other Fibres

Biodegradable and sustainable products are being employed to make contributions to efforts concerning environmental protection and the reduction of oil consumption. Biodegradable fibres present a simple and notable opportunity for providing sustainable textiles. Soybean fibre is a kind of regenerated and new-generation protein plant fibre. The present work aimed to analyse the many different properties of soybean fibres. Particularly it was focused on their performance, functional, comfort and dyeing properties. In literature, there are studies regarding soybean fibres but topics mostly involved the analysis of comfort properties of the fibre. In this study, fibre structure and composition, flame and UV resist ance, strength, pilling behaviour, air and water vapour permeability, water absorption, drape and dyeing properties were studied. It was indicated that soybean fibre is capable of meeting the performance, comfort and functional requirements of classical and technical textile products. The fibre has many of the good qualities of natural fibres such as tenacity, moisture regain, soft-lustrous handle, dyeability and colour fastness properties, and also has some of the functional properties of synthetic fibres such as being flame retardant and anti-ultraviolet.

A study on siro-jet spinning system

Nowadays, there is ever increasing interests regarding with the nozzle usage in spinning systems and also winding process. In this study, an air nozzle was attached on to the sirospun spinning system and the system was called as siro-jet. Sirospun is a spinning system combining spinning and doubling in one operation and a yarn like a two fold is produced. The principle of the siro-jet system is based on the placement of the nozzle at the exit of drafting unit on sirospun spinning system and pressurized air was fed into the nozzle by the compressor during the spinning. In literature, air nozzle application in this manner is not common and hence the system is very less known. For that reason, siro-jet and siropun yarns were produced with different fibre types, material qualities and yarn counts, and the properties of the yarns were compared. At the end of the study, it was determined that siro-jet spinning system truly improves the yarn hairiness in comparison to sirospun spinning system. Even, the siro-jet yarns are less hairy after winding process. Interestingly, hairiness results of siro-jet and sirospun yarns produced with short, non-uniform fibres showed that siro-jet spinning system allows working with low cost raw materials while maintaining yarn quality. Therefore, siro-jet can be considered as an innovative spinning system regarding with less hairy yarn production opportunity.

Analysis of Morphology, Luminescent Properties and Illuminating Durability of Photoluminescent Fibre

Bu calismada, luminesans malzeme iceren iplik ve kumas numunelerinin morfolojisi, yuzey ve gerilme ozellikleri ile parlama yogunlugu ve emisyon (yayinim) bozunma karakterleri analiz edilmistir. Luminesans (parlayan) iplik ve kumaslari dort farkli isik turu (UV, TL84, D65 ve F) ile 1 ve 5 dakika olmak uzere iki farkli surede aktive (sarj) edilmistir. Aktivasyon suresi, isik turu, numune formu ve agirliginin, baslangic isik (parlama) yogunlugu ve parlakligin zamana bagli olarak degisimine etkisi belirlenmistir. Calismada, gunluk kullanim veya tekstil prosesleri sirasinda karsilasilan surtme ve yikama etkilerinin parlama ozelliklerine etkisi incelenmistir.

Development of a novel hybrid yarn production process for functional textile products

In this study, an innovative method consisting of electrospinning and conventional textile production techniques was built up to produce hybrid yarns enabling the production of functional textile products. The principle of the developed method is to open the twist of spun yarn, make this fibre bundle conductive for use as a collector, collect the electrospun nanofibres onto the conductive opened fibre bundle and finally twist this structure to produce hybrid yarn. To determine the feasibility of the developed method, surface morphology, chemical composition, coating features and tensile properties of the hybrid yarns were compared with that of the pure yarn and nanofibre-coated yarns produced without untwisting and retwisting processes. Test results demonstrated that untwisting process in hybrid production method provided the application of nanofibres interior structure of the spun yarn while retwisting process made integration of classical textile fibres and nanofibres together and hence locking the obtained yarn structure effectively. Thanks to the integrated structure, it was successful to get the yarn have the required tensile properties for weaving, knitting and other processes. Three minutes was determined as the optimum coating time for the effective nanofibre deposition and tensile properties. Summing up the results, it was believed that the method helps to benefit from the special properties of nanofibres for the functional yarn production together with durability and higher tensile properties of the spun yarns for larger usage areas. The presented findings could encourage the researchers to commercialize the method in order to get nanofibre-coated functional yarns.

rPET Atıkları Kullanılarak Bor, Zeolit ve Pomza Partikül Takviyeli Nanokompozit Üretimi

Cevrenin korunmasi bakimindan atiklarin geri kazanilmasi ve hammadde kaynagi olarak tekrar kullanilmasi icin yontemlerin gelistirilmesi buyuk onem arz etmektedir. Bu calismada da, gunluk yasamda ve endustriyel urunlerde cok yaygin bir sekilde kullanilan polietilen tereftalat (PET) atiklarindan kaynaklanan kirliligin onlenmesi, plastik uretiminde atik haline donusen kismin efektif bir sekilde degerlendirilebilmesi ile birlikte geri donusum ve kompozit malzemelerin oneminden yola cikarak nano boyutlu cesitli partikuller iceren geri donusum PET (rPET) esasli nanokompozitlerin uretimi ve cesitli ozelliklerinin analizleri gerceklestirilmistir. Calismada, geri donusum PET polimerleri ile nanopartikuller (bor, zeolit ve pomza) eriyikte birlestirme veya eriyikte harmanlama metodu kullanilarak cift vidali ekstruder icerisinde %3 oraninda karistirilmis ve granul halinde nanokompozitler elde edilmistir. Calismada, partikul icerikli nanokompozitlerin polimer-partikul etkilesimi konusunda fikir sahibi olmak amaciyla bazi ic yapi ve termal ozellikleri incelenmistir. Bor, zeolit ve pomza icerikli nanokompozit uretimi konusunda on bir arastirmanin gerceklestirildigi calisma sonucunda, kullanilan partikul turune ve partikul dagilimina bagli olarak farkli degisimlerin meydana geldigi belirlenmistir.

Comparison of the Effects of Different Cotton Fibre Wastes on Different Yarn Types

In order to make a contribution to the reduction of raw material costs, in the present study the effect of reused cotton fibres on the quality of conventional ring and OE-rotor yarns was investigated. In the yarn production, three different waste fibres were taken from a cotton yarn production line and blended with primary cotton fibres at five different levels varying from 5% to 40%. In literature, studies have concentrated on the usage of recovered waste fibre in OE-rotor yarn production. However, to date there has been limited extensive and comparative research on the effect of recovered fibre quality on different yarn properties to determine the possibility of high-quality yarn production from reused fibres. In the study, we focused on the effect of different waste types as well as the amount of waste in the blends on the properties of different yarn types.