Development of graphene oxide added yarn

The aim of this thesis is to develop graphene oxide added yarns that can be used in wearable electronics. For this purpose, graphene oxide synthesized from graphite by the improved Hummers method was combined with thermoplastic urethane (TPU) and graphene oxide yarns were produced by wet spinning method. Graphene is a smart material with excellent mechanical, electronic, thermal, barrier, optical and chemical properties such as high surface area, superior thermal conductivity, high electron mobility, high Young's modulus, excellent light transmittance and chemical stability. In the literature, it can be produced by many methods, especially the exfoliation method and chemical vapor deposition method (CVD). Graphene oxide (GO) is a form of graphene sheets modified with oxygen-containing functional groups. The improved Hummers method is one of the most widely used methods for obtaining graphene oxide from graphite due to its ease of processing, low cost and scalability. In the thesis study, the effects of binder polymer ratio, needle diameter and coagulation bath on yarn production and properties were examined. For this purpose, FT-IR analysis, thickness measurement, electrical conductivity measurement and optical microscope analyzes were carried out. As a result, when the electrical and physical properties of the developed graphene oxide added yarns were examined, it was observed that as the TPU ratio increased, although better thread formation was observed, there was a decrease in the electrical conductivity values since TPU is an insulating polymer. The highest conductivity value was obtained in the 3rd trial (0.62 x 10-4 ±0.098 S/m). The electrical conductivity value of the 5th Trial was measured as the lowest and was obtained as 0.42 x 10-4 S/m. The resulting graphene yarns, thanks to their cost-effectiveness, flexibility, environmental friendliness and conductivity, will find use in the development of flexible/wearable products, devices that produce or store energy, and technical textiles by combining them with electronic textiles in the future