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Polyurethane (PU)-polypyrrole (PPy) composite films and nanofibers were successfully prepared for the purpose of combining the properties of PU and PPy. Pyrrole (Py) monomer was polymerized and dispersed uniformly throughout the PU matrix by means of oxidative polymerization with cerium(IV) [ceric ammonium nitrate Ce(IV)] in dimethylformamide. Films and nanofibers were prepared with this solution. The effects of the PPy content on the thermal, mechanical, dielectric, and morphological properties of the composites were investigated with differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), Fourier transform infrared (FTIR)-attenuated total reflection (ATR) spectroscopy, dielectric spectrometry, and scanning electron microscopy. The Young's modulus and glass-transition temperatures of the composites exhibited an increasing trend with increases in the initially added amount of Py. The electrical conductivities of the composite films and nanofibers increased. The crystallinity of the composites were followed with DSC, the mechanical properties were followed with DMA, and the spectroscopic results were followed with FTIR-ATR spectroscopy. In the composite films, a new absorption band located at about 1650 cm À1 appeared, and its intensity improved with the addition of Py. The studied composites show potential for promising applications in advanced electronic devices.

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The oxidative polymerization of pyrrole (Py) by cerium(IV) on Poly(Acrylonitrile- co-Vinyl Acetate) matrix was performed. Nanofibers were obtained from this solution by the electrospinning method. A new absorption band was observed corresponding to the CH in plane vibration of polypyrrole (PPy) by Fourier transform infrared-attenuated total reflectance spectrophotometric analysis. A linear relationship was determined between the absorbance ratios of functional groups corresponding to the conjugated polymeric units and initial Py concentrations in the presence and absence of Py. Scanning electron microscope images indicated that the diameters of nanofibers were dependent on PPy content and that the average nanofiber diameters were reduced with increasing the initially added Py concentration. The alternating current conductivity of nanofibers was increased with frequency, particularly in the higher frequency region (> 105 Hz).

The adhesion strength enhancement of oxygen plasma pre-treated laminated polypropylene nonwoven fabrics using two different types of adhesives was investigated in this study. Fabric surface modification was performed using low-pressure, radio-frequency oxygen plasma treatment. Effect of plasma treatment on fabric surface wettability was determined by vertical wicking measurements. Wettability of highly hydrophobic polypropylene nonwoven samples dramatically increased with increasing plasma power and exposure time. Plasma-treated polypropylene fibers showed rougher surfaces with increased plasma power and treatment times. X-ray photoelectron spectroscopy (XPS) analysis showed that oxygen plasma treatment of polypropylene fiber surface led to a significant increase in atomic percentage of oxygen compound responsible for hydrophilic surface. Peel strength enhancement of produced laminated fabrics was observed for plasma-treated samples compared to untreated samples. PU-based adhesive attached on the surface of both plasma-treated and untreated polypropylene nonwoven, filling the spaces between the fibers due to the penetration of the adhesive agent. The improvement in surface wettability of polypropylene nonwoven and the introduced sites through oxygen plasma treatment resulted in good adhesive bonding. For both adhesives, peel strength improvement of produced laminated fabrics was

In this study, velour design molded automotive carpets made of recycled polyethylene terephthalate (PET) fibers were developed via needle-punching process to improve their abrasion resistance properties. Initially, virgin PET fibers and recycled PET (rPET) fibers derived from PET bottle wastes were supplied from different producers and they were tested in terms of their fiber properties such as fiber length, crimp, tensile strength, elongation, tenacity, and intrinsic viscosity. It was demonstrated that recycled fibers from bottle wastes used in the study have lower tenacity and higher elongation than virgin PET fibers. In the second part, rPET fibers to be used in manufacturing in terms of their desired properties were selected. Subsequently, molded automotive carpets were produced from the selected rPET fibers and virgin PET fiber blends with adjusted manufacturing and molding parameters. Developed carpets were tested for abrasion resistance performance and they were evaluated according to requested specification. Results showed that carpets made of 85% rPET + 15% bicomponent PET had almost equal performance in terms of both fiber loss and carpet appearances with carpets consisting of 80% PET + 20% bicomponent PET. Carpets made of recycled PET fibers offer the manufacturer low raw material costs in addition to ecological advantages.

This work aimed to produce poly(acrylonitrile-co-itaconic acid) (P(AN-co-IA)) nanocomposites with poly(3,4ethylenedioxythiophene) (PEDOT) and poly(3-methoxythiophene) (PMOT). An anionic surfactant sodium dodecyl benzene sulphonate was used in emulsion polymerization for nanocomposite production. Incorporations of PEDOT and PMOT on the nanoparticles were characterized by scanning electron microscopy (SEM), atomic force microscopy, Fourier transform infrared-attenuated total reflectance spectroscopy and ultraviolet spectroscopy. These nanoparticles were blended with PAN and the blends were electrospun to produce P(AN-co-IA)-polythiophene-derivative-based nanofibres, and the obtained nanofibres were characterized by SEM and energy dispersive spectroscopy. In addition, electrochemical impedance studies conducted on nanofibres showed that PEDOT and PMOT in matrix polymer P(AN-co-IA) exhibited capacitive behaviour comparable to that of ITO-PET. Their capacitive behaviour changed with the amount of electroactive polymer.

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