Iwona Karbownik

Deposition of one-dimensional zinc oxide structures on polypropylene fabrics and their antibacterial properties

In this article, a new method of modification of polypropylene fabric surface is presented, in order to obtain a material with antibacterial properties. The surface of the fabric is modified by direct deposition of the hexagonal zinc oxide rods onto the surface. For this reason, the influence of temperature on the size and morphology of microstructures of ZnO was investigated. Deposition was carried out at two temperatures, 75 and 90℃. The surface of the fabrics was treated with oxygen plasma. The influence of oxygen plasma on the parameters of rods was examined. The microstructure and crystalline structure of ZnO rods were investigated by scanning electron microscopy and X-ray diffraction. In addition, the impact of morphology and size of obtained ZnO structures on the biological activity of modified materials was determined. The tests revealed that the modified fabric shows very good antibacterial activity.

Textile materials for electromagnetic field shielding made with the use of nano- and micro-technology

Studies have been carried out aimed at the development of structures and technology for making special multi-layer textile-polymeric systems of shielding electromagnetic field (EMF). The use of textiles as EMF shielding materials is commonly known, however the EMF attenuation obtained practically exclusively results from the reflection of EMF, while the materials used for this purpose as a rule, show poor EMF absorption abilities. The basic assumption for a new solution is the exploitation of the multiple internal reflection of incident EMF either in textile-polymeric coating materials containing fine-particle electromagnetic materials or in special textile structures. This paper presents the results of investigating the EMF shielding effectiveness of several selected and developed textile-polymeric materials in respect of both their practical applications (protective clothing elements, technical materials, masking elements, etc.) and the structure and content of components with various EMF reflection and absorption properties. The measurement method for independent determination of reflection and transmission coefficients with a wavequide applicator was used. The results obtained with the 2.5 GHz to 18 GHz frequency range show a low value of transmission coefficient (min. −35 dB) and accepted reflection attenuation from about −4 dB to −15 dB for higher frequencies.

Light, multi-layer, screening textiles with a high capacity for absorbing electromagnetic fields in the high frequency range

Abstract This paper concerns multilayer, shielding textile-polymeric materials with a high shielding effectiveness. This effectiveness is characterised by a high capability to absorb electromagnetic fields as a result of intensification of multiple internal reflections at the boundaries between the layers of component materials. These new shielding materials present low thicknesses and surface weights, amounting to 1.0–2.0 mm and 190–420 g m−2, respectively, depending on their structures. Such materials composed of various structures, containing various functional particles, meet high requirements of shielding effectiveness within the frequency range tested from 8.0 to 18.0 GHz. Their absorption coefficient is at a level of ≥ 30%, and in some structures it even exceeds 90%, while the reflection coefficient is ≤ 20% and that of transmission amounts to as low as ≤ 20%, approaching even below 2%.

PAN fibers with nanoprecipitated Ag and Au for use in textronics

Abstract Silver and gold nanoparticles have been linked with the structure of polyacrylonitrile (PAN) fibers as a result of a synthesis. The nanoparticles were formed in the dimethylformamide (DMF) solution, which is uncommon for their synthesis, but is a typical solvent for polyacrylonitrile. The examination of metallic nanoparticles doped fibers showed the presence of these particles in the samples. Analysis of Energy Dispersive X-ray Spectrometry (EDX) results showed that silver content in the fibers was the same as in the precursors of metal ions. The amount of silver in the fibers was significantly greater than the amount of gold in the corresponding sample. The Dynamic Light Scattering Method (DLS) and Visible and Ultraviolet Spectroscopy (UV-Vis) analyses indicated a difference between the sizes of metallic nanoparticles. The obtained composite polyacrylonitrile fibers doped with silver and gold nanoparticles were characterized by high flexibility and reduced electromagnetic radiation. The authors are convinced that the results obtained during the research will considerably contribute to the development of textronics discipline.