Polypyrrole was deposited on polyester yarns by vapour phase polymerization technique. Ferric chloride was used as an initiator. In order to determine the effect of the initiator concentration on polymerization process, four different initiator concentrations (0.2, 0.4, 0.6 and 0.8 mol/l) were used. The effect of the initiator in terms of tensile properties, electrical resistivities and morphological properties of the yarns was investigated. The polypyrrole deposited polyester yarns were then weaved in a handloom to form fabric for the investigation of surface resistivity and electromagnetic shielding effectiveness. Scanning electron microscopy, energy dispersive spectroscopy and Fourier transform infrared analyses illustrated that polypyrrole has penetrated into the yarn structure and the highest polypyrrole deposition was obtained at the initiator concentration of 0.6 mol/l. Also, the highest electromagnetic shielding effectiveness value and the lowest surface resistivity were obtained at this concentration.

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In this study, bisphenol-A-based acrylated epoxy oligomers were prepared and utilized to improve the adhesion strength of polyester cords onto rubber. The structure of the oligomers was characterized by Fourier transform infrared spectroscopy and 1 H-NMR spectroscopy. Ultraviolet-curable adhesive formulations were prepared by using acrylated epoxy oligomers and applied onto the polyester cord fabric by a dip-coating method and irradiated. Ultraviolet-cured coatings were characterized by thermal and scanning electron microscope analysis, contact angle measurements. In the second stage of the experiment, ultraviolet-cured polyester cords were adhered onto rubber under heat and pressure. The prepared adhesive formulation was expected to improve the adhesion strength. The adhesion strength of the coated material was evaluated by using peel test as a function of the carboxyl/epoxide ratio. The adhesion strength of 18.0 N/cm was obtained when the carboxyl/epoxide ratio was set as 1. It was observed that peel strength, contact angle, and surface energy values of acrylated epoxies strongly depend on the acrylic acid content of the oligomer.

Electrospinning was used for the coating of the polyurethane/silica hybrid solutions on the cotton fabric surface. An ultraviolet curing process was performed on the collector by an ultraviolet lamp positioned inside the electrospinning cabin. In order to investigate the effect of fluorinated, silane-functionalized urethane (inorganic part) content on the water-repellency; five different fluorinated concentrations (10%, 20%, 30%, 40%, and 50% by weight) were used. The disappearance of isocyanate peaks during the silane-functionalized urethane synthesis was observed by Fourier transform infrared spectroscopy. Surface morphology and elemental analysis of the coated cotton fabric surfaces was investigated by scanning electron microscopy and energy dispersive spectroscopy analysis respectively. Water-repellency was evaluated by contact angle measurements. A sample that contained 50% inorganic part showed a contact angle of 154.5°. Samples were thermally characterized by differential scanning calorimetry. Glass transition temperature of the synthesized hybrid polymer increased with increasing inorganic part ratio. Additionally, abrasion resistance and crease recovery angle tests were performed to evaluate the effect of fluorinated part percentage on the mechanical and comfort properties of fabrics.

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In recent years, the importance of laboratory applications in engineering education has increased because, there is need for transferring the theoretical knowledge to empirical research and practice, which is particularly significant for the development of students in their career. Therefore, the evaluation of these laboratory applications should be effective. In this study, we propose a new approach to this assessment system. Our approach uses fuzzy decision support system and proposes a new approach that is called 'refinement process' on student grades. Fuzzy helps more reliable decision making and evaluation of applications using a pre-determined list of criteria. This model based on fuzzy multi criteria method, is developed for evaluating student performances in laboratory activities which consolidate theoretical knowledge with practical applications. In our approach, we use peer assessment, group assessment and personal assessment methods. This study shows that fuzzy system can provide a better evaluation system than classical systems.