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

In this study, flame retardancy properties of fabrics treated with phosphorous (P) doped and undoped SiO 2 thin films were developed by sol-gel technique. As to this aim, P-doped and undoped SiO 2 film were coated on cotton fabric from the solutions prepared from P, Si-based precursors, solvent, and chelating agent at low temperature in air using sol-gel technique. To determine solution characteristics, which affect thin film structure, turbidity, pH values, and rheological properties of the prepared solutions were measured using a turbidimeter, a pH meter, and a rheometer machines before coating process. The thermal, structural, and microstructural characterization of the coating were done using differential thermal analysis/thermograviometry, fourier transform infrared spectroscopy, X-ray diffractometry, and scanning electron microscopy. In addition, tensile strength, wash fastness, flame retandancy, and lightness properties of the coated fabrics were determined. To compensate the slight loss of tensile strength of samples, which occurred at the treated fabrics with P-doped Si-based solutions, the cotton fabrics were coated with polyurethane films during second step. In conclusion, the flame retardant cotton fabric with durability of washing as halogen-free without requiring after treatment with formaldehyde was fabricated using solgel processing for the first time. Moreover the cotton fabrics, which were treated with P-doped Si-based solutions and then coated with polyurethane at second step, still has got nonflammable property.

Recently, the use of carbon nanotubes (CNTs) and fullerenes in the design of new biosensors have attracted great interest in the development of carbon nanomaterials. Due to the superior properties of CNTs and fullerenes, the use of sensor components allows the development of reliable, accurate and fast biosensors. Depending on the types of target molecules, the development and application areas of the sensors vary. This review summarizes the role of CNTs and fullerenes in the development of biosensors in different application areas. Considering the difference between other members of the nano-carbon family, we explain why CNTs are used more widely in biosensor applications and why fullerenes have high potentials in these areas of application. Moreover, we focused on investigating the function of these nano-carbons in the detection of various analytes in bio-sensing. By discussing the challenges and future expectations, we have put forward a perspective that may help synthesize advanced composites in the development of new generation designs in biosensor applications.

No abstract