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Intrinsically conducting polymer polypyrrole/polyester textile composites were prepared by in situ chemical oxidative polymerization of polypyrrole on a polyester fabric. As an oxidizing agent ferric chloride was used, p-toluenesulfonic acid was used as a dopant. Polymerization conditions (concentration of monomer, polymerization time and temperature) were investigated and optimized by the help of Design of experiment methodology to obtain fabric with electromagnetic shielding efficiency at least 12 dB for frequency 1.5 GHz. Moreover, weight increase, macroscopic color shade of images and scanning electron microscopy images of samples were evaluated. It was found that all selected factors and their interactions have statistically significant effect on resulting electromagnetic shielding effectiveness, whereas monomer concentration has the highest positive influence. Experimental data were used to derive an empirical model linking the output and inputs. Optimized parameters (polymerization temperature 6.7℃, polymerization time 10 h and monomer concentration 5.8 g/l) for creating polypyrrole/polyester textile composite with electromagnetic shielding ability higher than 12 dB were successfully verified.

This paper deals with problematic of preparation of iron oxide nanoparticles according to a self-combustion method. Iron oxide nanoparticles can be used e.g. for catalysators and gas sensors or in MRI. The Self-combustion method is based on rapid chemical reaction between a fuel and iron oxide precursor. Glycine, urea and citric acid were used as fuels and iron nitrate nonahydrate was used as an iron oxide precursor. The self-combustion method doesn't require any special equipment, is environment-friendly due to minimize pollution and the results are easily reproducible. The shape, size, and phase of resulting particles were investigated studied using scanning electron microscopy and energy-dispersive analysis.

Vapor deposition technique was employed to coat polypyrrole (PPy) on glass substrate using FeCl3as oxidant and p-toluenesulfonic acid (−OTs) as doping agent. The Joule heating effect of PPy coated E-glass fabric was studied by supplying various DC electric fields. The coated fabric exhibited reasonable electrical stability, possessed medium electrical conductivity and was effective in heat generation. An increase in temperature of conductive fabric subjected to constant voltage was observed whereas decrease in power consumption was recorded. Thickness of PPy coating on glass fibers was analyzed by Laser confocal microscope and scanning electron microscope.

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