For preparing the Pd nanoparticle (PdNP)-decorated heterogeneous catalyst material, wool fabric was utilized as a practical platform after enriching its chemical functionality with two straightforward chemical processes. First, wool keratin was transformed to a reduced structure (WSH) with NaHS by extracting −SH groups and then reconstructed to the S−S linkages by the covalent attachment of 2-amino thiophenol (2-ATP). The graft copolymerization of 2-ATP onto this 2-ATP/WSH surface was ensured to prepare a P2ATP-g-WSH copolymer fabric. As the second process, the polymerization of 2-ATP was also performed on the WSH fabrics to prepare a P2ATP/WSH composite. The PdNP anchoring was subsequently ensured onto these copolymer and composite samples through the in situ reduction of Pd 2+ to the PdNPs. The conditions yielding the highest PdNP content were investigated in detail, and the PdNP formation abilities of both fabrics prepared by different routes were compared. It was observed that the contribution of PdNPs through the P2ATP/WSH composite route was relatively high compared to that of the copolymer route. The structural and morphological alterations in the wool nature, the existence, the oxidation state, and the relative abundance (%) of PdNPs with respect to the Pd 2+ ions were evidenced by many techniques in detail. After examining the performance of the PdNP composites in the catalytic reduction of two nitroarenes to the aminoarenes, the Pd/ P2ATP/WSH demonstrated satisfactorily high performance in terms of reduction yield (%), reduction rate constant (min −1 ), and reusability, compared to that of Pd/P2ATP-g-WSH.

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A conductive polypyrrole/silver/poly(ethylene terephthalate) composite was prepared by the polymerization of pyrrole with AgNO3 oxidant in the presence of poly(ethylene terephthalate) nonwoven. The effect of AgNO3/pyrrole mol ratio and concentrations of the reactants was investigated on the polypyrrole/silver content and surface resistivity of the composite. The deposition of shiny metallic Ag particles was observed on the composite during the polymerization of pyrrole. The weight fraction of the Ag particles in the polypyrrole/silver contents of the composite was determined by thermogravimetric analysis. It was observed from scanning electron micrographs that the morphology of the polypyrrole/silver particles changed with the increase in the polypyrrole/silver contents of the composite. The electromagnetic shielding effectiveness as well as the absorption loss, reflection loss with the values of absorbance and reflectance, showing their contributions to the electromagnetic shielding effectiveness value of the composite were determined within the frequency range of 15–3000 MHz. An absorption dominant shielding was obtained with the value of 13–15.5 desibel for double coated composite.

A conductive polyaniline (PAn)-polythiophene (PTh)/poly(ethylene terephthalate) (PET) composite fiber was prepared by polymerization of aniline and thiophene in the presence of PET fibers in an organic medium with FeCl 3 . The effects of polymerization conditions, such as polymerization medium, mol ratios of aniline/thiophene and FeCl 3 /aniline-thiophene as well as polymerization temperature and time, were investigated on PAn-PTh content (%) and surface resistivity of the composite. The composite with the lowest surface resistivity (1.30 MX/cm 2 ) was obtained by polymerization of aniline and thiophene (1/3 mol ratio) in acetonitrile/ chloroform (1/5 volume ratio) at 20 C. The surface resistivity of the PAn-PTh/PET composite containing 4.8% PAn-PTh was increased from 1.9 MX/cm 2 to 270 MX/cm 2 at pH 11. The washing durability of the composites was determined with domestic and commercial laundering processes by monitoring the surface resistivity and morphology. The composite was also characterized with FTIR, TGA, elemental analysis, optic microscope and SEM techniques.

Wool has disulphide bonds containing-hydrophobic external keratin layers, which act as a barrier for the modification through coating with hydrophilic materials. For that reason, in this work, to ensure a dense and homogenous conductive polymer coating onto the wool, the fabrics were subjected to the reduction process in the aqueous alkaline medium containing agents that can attack these disulphide bonds. Then, one of the polyaniline derivatives, poly(mtoluidine) (PMT), was coated onto wool by in situ polymerization of m-toluidine sulphate using ammonium persulfate (APS) as an oxidant. The effects of conditions, such as the composition of reduction-bath and types of dopants were investigated, on the mass increase (%) and surface resistivity of the composite. The reduction pretreatment of wool with sodium hydrosulphide significantly improved the coating density, conductivity, and colour shade of PMT on the surface, compared to an untreated one. The coating stability of PMT/wool composite was examined by rubbing test and detergent washing, through surface resistivity measurements. The changes in structural and surface properties of wool fabrics were determined with ATR-FTIR, contact angle, and optical microscopic techniques, respectively. The performance of PMT/wool composite was also examined in the electromagnetic shielding effectiveness (EMSE) measurements within 30 MHz-3 GHz.