Elektromanyetik Dalga Engeli Tekstil Ürünleri Üzerine Bir Araştırma: Polimer Kaplama Ve Yüzey – Arayüzeyler İle İlgili Yapısal İncelemeler

Abstract

Nowadays, in the environment that we live, the radiation pollution caused by common applications such as high voltage power lines, communication and radar systems, systems used for diagnosis and cure in medicine increase every day. Especially, negative impacts like the existence of harmful electromagnetic waves (EMW) coming from space and effective on air transportation, the increasing thickness of the ozone layer and the expansion of the ozone hole etc. indicate that humankind will face much more harmful effects of EMW. In order to avoid these harmful effects of waves/radiation, some companies are carrying out important R&D activities on textile. Several textile products manufactured from composite and nanofiber materials which have organic, organometallic compounds and potential to prevent EMW. Textile products should be coated with polymer to avoid such disruptions and negative external impacts may occur during use which may disable the EMW shield. With this thesis study carried out in SWAXS Research Team of Hacettepe University Physics Engineering Department, at first, the complex structures of EMW shield textile products in the market were examined in nanoscopic scale with using Small Angle X-ray Scattering (SAXS). Pioneering work done with two types of a textile product as defined by the codes SG (Steel Gray) and ST (Silver Twin) focused on. When selecting these two products, we choosed the most powerful EMW shield and antibacterial properties products carefully. In addition, whether they are also suitable for the surface properties of the polymer coating operations, Atomic Force Microscopy (AFM) was determined using the method. Following those, coating studies were carried out by using a special plastomer (plastidip) doped with carbon nanotube and graphene which inside 2D and 3D nano particles. Prepared with graphene and carbon nanotubes at different rates into dissolved private polymer, a spray method was applied on textiles to coating. After coating, the change in textile products’ EMW shield, structural changes in their interfaces and their surface were examined from Angstrom to nanoscale and then, from nanoscale to microscale. Mainly method was used SAXS for surface and inter surface structures. Then, were tested Waveguide Methods for changing coated textiles EMW shielding efficiency. These materials which can be directly available for human consumption were determined if they created a problem in terms of human health, bio activity before/after coating fabric. An interdisciplinary study within the scope of this thesis, we collaborated with valuable scientist of Department of Electrical and Electronics Engineering and Department of Biology of Hacettepe University. In the results of the study, for the first time such textile materials related to nano-scale structural R & D activities performed and polymer which doped CN and Graphene coating operations in the range 0-13 GHz made with the shielding properties and anti-bacterial effects can be associated with the structure of the nano-composite products could be obtained. Graphene-doped polymer-coated fabric on the surface of nano-fractal structures formed, on the other hand, CN-doped polymer-coated fabric on the surface of Core Shell Cylinder nano-structures have revealed. The formation of dispersed nano-graphene on the surface with the fractal model have caused to be obtained a uniform distribution on the surface smooth and EMW shielding has contributed to achieve more uniform at each point of the surface of the property. Coatings on ST fabrics for both grafene and CN were obtained much more smooth and homogeneous. In this case, it is verified by AFM and EMW interaction tests. %4 CN-SG textile products have the highest value for absorption for 11-13 GHz EMW has the highest value for absorption according to uncoated SG and has shown that have a minimum of reflection of the material used in the study of invisibility in the region of this frequency. Absorption value of the coated sample respect to uncoated one was increased from 0.2 to 0.3 and so, 50% development was obtained by coating. %4 Graphene–SG is a maximum reflectivity in the range of 8.5 to 13 GHz for EMW beside materials permeability and absorption are a minimum. So, SG is better shielding property which was obtained according to the starting material. Transmission value was increased from 1.2 to 0.5 with 33% development after the coating. %2 CN-ST material is high reflectance, low absorption and permeability in the range of 8 to 13 GHz. Therefore EMW shield has the distinction of being important as a product. Transmission value was decreased from 2.2 to 0.5 with 77% increasing after the coating. %2 Grafen-ST fabric materials are maximum reflectance, minimum absorption between in the range of 9.8 to 13 GHz and it is revealed that much less compared (from 2.8 to 1.4 with 50% increasing) to an uncoated fabric is permeable. At the same time, this textile products have effective bio-activity on Gr(+) Staphylococcus aureus and Gr (-) Escherichia coli microorganisms. It was determined that when CN doping rate of CN doped ST materials increased, Rg semi-diameter values (8.96 – 11.80 nm) and cluster size (24.63 – 34.29 nm) also increased at the nanoscale. The most valuable product obtained as a result of this study in terms of physical, chemical and biological properties was a 2% CN-ST material. 8.96 nm half-scale homogeneous dispersion of globular particles of the material is the best EMW shielding and also it has a very good anti-microorganism capability.