In this study, the structural, electrical, and electromagnetic properties of cotton fabrics coated with polyaniline (PAni) and polypyrrole (PPy) were investigated and compared. For the aims, anilin and pyrrole were used as monomers, and in situ polymerization on cotton fabric by chemical oxidative polymerization was performed. After production, the structural properties of the fabrics were determined with Fourier transform infrared spectroscopy and X-ray diffraction. In addition, ultraviolet (UV) permeability, tensile strength, colorfastness, and electrical and electromagnetic measurements of the fabric samples were carried out. The resistance values of the cotton fabrics coated with PAni and PPy were found to be 350 and 512 X, respectively. The average electromagnetic shielding efficiency and average absorption values of the cotton fabrics coated with PAni were determined to be 3.8 dB and 48%, respectively, and these values for the cotton fabrics coated with PPy were 6 dB and 50%, respectively. Consequently, a significant difference was not observed between the resistance values and electromagnetic parameters of the fabrics coated with PAni and PPy, although the intact textile characteristics of the fabric coated with PPy were protected and improved, whereas the characteristics of the fabric coated with PAni were inferior. Moreover, we first report that the fabrics coated with conductive polymers had excellent UV-protection properties.

In this study, we aimed to produce fabrics with microwave absorbing properties in broad band. For this purpose, the cotton fabrics were coated with polyaniline (PAni) by using chemical oxidative polymerization method. Firstly, the type of protonic acid used, the polymerization time, the type and concentration of dopant, and the number of coating layer were varied as parameters. The effect of these parameters on resistance values of coated fabrics was investigated. We determined the most appropriate process conditions to provide the lowest resistance values. Secondly, the fabric was coated with PAni by adding barium ferrite powder as filler with different ratios. Morphological properties, electrical, and electro-magnetic properties of coated fabrics were determined. As a result, we obtained 350 X of the minimum resistance values of coated fabric using 1M HCl, 0.5M aniline and 0.5M ammonium persulphate by chemical oxidative polymerization method for totally 4 h of polymerization time. The results of electromagnetic parameters showed that the absorption values of the fabric coated PAni was average 48% in the frequency range of 6-14 GHz. It was concluded that microwave absorber for a textile material can be successfully produced by this process. V

Hydroxyapatite (HAP) coatings are applied on metallic implant materials to combine mechanical properties of metallic material with bioactivity abilities of HAP ceramic. In this study, HAP coatings with additions of Si and Mg are proposed to be deposited on Ti6Al4V substrates by RF magnetron sputtering. Chemical bonding, morphology, topography and corrosion resistance in simulated body fluids (SBF) of the coatings were investigated. Additionally, mechanical and biological properties of the coatings were evaluated. It was found that the addition of Si and Mg does not influence the formation of a HAP phase. All the coatings exhibited smooth surface and uniform growth, without defects or cracks. Both hardness and elastic modulus of the coated samples decrease with Mg addition in the HAP-Si structure. Both Mg and Si addition into HAP coatings were found to enhance the corrosion resistance of the Ti6Al4V alloy in the SBF solution. Coatings with low Mg content exhibited better corrosion performance. All the coatings investigated were biocompatible, as demonstrated by SaOS-2 bone cell attachment and growth. However, cell proliferation and morphology were inferior on samples with the highest Mg content.

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