Nuray UÇAR, Gökçen GÖKÇELİ, Nilgün KARATEPE, Ayşen ÖNEN

DİSPERSİYON HAZIRLAMA TİPİ VE SON KOAGÜLASYON BANYOSUNUN YAŞ ÇEKİM METODU İLE ÜRETİLEN GRAFEN OKSİT LİFLERE ETKİSİ

Grafen oksit (GO) lifi, yüksek elektrik iletkenliği, uygun termal ve mekanik özellikleri ve üretim kolaylıkları sebepleri ile oldukça ilgi çekici bir konumdadır. Enerji, sensor, katalist vb. pek çok alanda kullanım potansiyeline sahiptir. Çok yakın bir zamanda, yaş çekim metodu ile üretilen GO lifleri üzerine çalışmalar başlandığından, oldukça kısıtlı sayıda çalışma literatürde mevcuttur. Bu çalışmada ise, farklı süre ve farklı devir/dakika ’da GO dispersiyonu hazırlanmış, son koagülasyon banyosunda ise farklı oranda aseton kullanılmıştır. Böylece, ilk defa, GO dispersiyonu hazırlama metodunun ve son koagülasyon banyosundaki aseton oranının, GO lifinin mekanik ve elektrik iletkenliği üzerine olan etkisi incelenmiştir. GO dispersiyonunun hazırlanmasında uygulanan devir/dakikanın, dispersiyon süresine kıyasla mekanik özellikler üzerine etkisinin çok daha fazla olduğu görülmüştür. Son koagülasyon banyosu %100 aseton olan numunelerin mekanik özellikleri, %80 aseton-%20 su içeren numunelere göre daha düşüktür. Numuneler arasında, en yüksek mekanik özellikler, CaCl2-etanol ile koagüle olan ve dispersiyonu 15 000 devir/dakika, 90 dakika şeklinde hazırlanan numunelerde görülmüştür. Diğer taraftan NaOH-aseton ile koagüle edilen numuneler en düşük mekanik özelliklere sahip olmuştur. Tüm numuneler elektrik iletkenliği bakımından yarı iletken malzeme grubuna girmektedir (10-4 S/cm)

Anahtar Kelimeler:

Grafen Oksit Lifi, Yaş Çekim Metodu, Koagülasyon Banyosu, Dispersiyon Oranı, Dispersiyon Süresi

THE EFFECT OF DISPERSION PREPARATION TYPE AND LAST COAGULATION BATH ON GRAPHENE OXIDE FIBERS PRODUCED BY WET SPINNING TECHNIQUE

Graphene oxide (GO) fiber is a promising material because of its unique properties such as high electrical conductivity, good thermal and mechanical properties and scalable production. It can have widespread usage area such as energy storage devices, sensors, catalysis, biological applications. As seen from literatures, the studies on GO fiber produced by wet spinning technique are very limited because only a few years ago, the studies on this area were started. In this study, different dispersion rate, different dispersion time and different content of acetone in the last coagulation bath have been studied. Thus, for the first time, the effect of preparation method of GO dispersion and the content of highly evaporative solvent in the last coagulation bath on mechanical and electrical properties of GO fiber have been examined. It has been seen that dispersion rate has higher positive effect on mechanical properties than dispersion time. The samples lasted by %100 acetone coagulation bath have a lower mechanical property than the sample lasted by % 20/80 (distilled water/acetone). Among samples, highest mechanical properties belong to sample with coagulated by CaCl2-ethanol and dispersed for 90 minute by 15 000 rpm. Meanwhile coagulated samples with NaOH-acetone had the lowest mechanical properties. With regard to electrical conductivity, all samples are in the semi conductive range (10-4 S/cm)

Keywords:

Graphene Oxide Fiber Wet Spinning, Coagulation Bath, Dispersion Rate, Dispersion Time, Electrical Conductivity,

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