No abstract

Direct conversion of nanofibers into a yarn formed by electrospinning has begun to draw attention recently while pioneering attempts in fact go back to 1930s. Once nanofiber yarns are spun successfully by electrospinning, obviously, this would open new gates for many different applications. However, this is still a challenging task and there is no system accepted universally yet. There are more than 20 different approaches available so far but with serious limitations. In this review, they were categorized as (i) systems for production of parallel bundle of nanofibers and (ii) systems for production of twisted nanofiber yarns, presenting potential applicability of each with a critical point of view. The results show that some of the attempts mainly present basic conceptual ideas only. There are some works to produce real twisted nanofiber yarns continuously while mainly funnel, disc, or ring collectors have been used as the twisting element. However, there is limited information regarding stability of spinning system or control of yarn properties. This review also analyses the technical properties of electrospun nanofiber yarns summarizing the available data in terms of yarn properties such as fiber fineness, twist, production speed, mechanical properties, polymer types, and other important parameters available.

No abstract

There is a group of animal fibers known as "luxury fibers." These are mohair, cashmere, camel hair, lama, alpaca, vicuna, guanaco, angora, yak, and quivit. In this study, the effects of demographical variables such as gender, education, age, sector, and income on the recognition and usage of luxury fibers in Thrace Region of Turkey were investigated. In order to analyze the obtained data, crosstabulation and chi-square statistical methods are used. According to the experimental results it can be said that the most commonly known and used luxury fibers are cashmere, mohair, and angora. The most important (37.6%) reason for participants to use luxury fibers is their warm feeling. On the other hand the most important (approx. 30%) reason for participants not to use them is that they do not have sufficient information about these fibers. It was determined that the most commonly (37.8%) used textile product made of luxury fibers is outerwear. Furthermore, it was found out that approximately 75% of participants accept paying more for garment containing luxury fibers because of their high quality.

Elektrik alan ile lif çekimiyle nanometre ölçeğinde inceliğe sahip elyaf üretimi, liflerin sağladığı üstün performans yanında kullanılan yöntemin basit olması ve esnek üretim şekli nedeniyle son yıllarda yaygın bir uygulama haline gelmiştir. Ancak mevcut uygulamalarda genel yaklaşımın, liflerin doğrudan ağ-doku oluşturacak şekilde dokusuz bir yüzey halinde üretim olması, yüksek özellikli söz konusu özel liflerin kullanım alanını sınırlamaktadır. Oysa bu yöntemle üretilen liflerin kesintisiz uzunlukta direkt iplik halinde eğrilebilmesi sağlandığı takdirde, bu liflerin dokuma veya örme yüzey haline dönüştürülmesi ve bu sayede ürünlerin çok daha geniş bir kullanım alanına kavuşması mümkün olacaktır. Bu amaç doğrultusunda sunulan çalışmayla, elektrik alan ile lif çekimiyle iplik üretimi konusunda henüz sınırlı sayıdaki mevcut özgün yaklaşım ve yöntemler; (i) nanoliflerden paralel lif demetleri halinde iplik eğirme yöntemleri ve (ii) nanoliflerden bükümlü iplik eğirme yöntemleri olmak üzere iki temel gruba ayrılarak incelenmektedir. Çalışmada ortaya konan bulgular; uygun eğirme yöntemi, uygun hammadde ve üretim parametrelerinin seçimi sonucu nanolifleri içeren özel ipliklerin arzu edilen incelik, büküm veya fonksiyonel özelliğe sahip olacak şekilde nihai amaca uygun şekilde tasarlanabileceğini ve eğirilebileceğini göstermektedir. Anahtar Kelimeler: Nanolif iplikler, elektrik alan ile lif çekimi (electrospinning), paralel lif demetleri halinde nanolif iplik eğirme, bükümlü nanolif iplik eğirme NANOFIBER YARN PRODUCTION METHODS BY ELECTROSPINNING ABSTRACT: Nano-size fiber production by electrospinning has been a common application method recently due to both being an easy and flexible system and high performance of the fibers produced. Generally in this system, fibers are produced directly as a non-woven surface of fiber-web and this limits potential end-uses of these high performance fibers. However direct spinning of these special fibers into a yarn form rather than production as a web-surface by electrospinning method would lead to an easy conversion of these fibers into woven or knitted fabrics and therefore widen the use area of these fibers substantially. In this respect, this work describes the novel approaches and methods for nanofiber yarn production by electrospinning classifying available but limited studies into two main categories: (i) parallel bundle of nanofiber yarn spinning methods, and (ii) twisted nanofiber yarn spinning methods. The results show that these highly special nanofiber yarns, which can have desired fineness, twist and functionality, could easily be designed and spun for a specific enduse by careful selection of the spinning method, choice of polymer and production parameters.