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The aim of this study is synthesis of polyurethane (PU) composites from 4,4′-methylenebis(cyclohexyl isocyanate), 1,2-ethanediol and different amounts of copper-based polyoxometalate (Cu-POM) and investigation of their dielectric properties. Firstly, Cu-POM structure as reinforcement was synthesized with ammonium heptamolybdate and Cu metal ion salt by a hydrothermal synthesis method. Then, Cu-POM-PU composites were prepared by in situ polymerization process. The prepared Cu-POM-PU composites were characterized by means of various techniques for their structure, morphology and thermal behaviour. The chemical structure, surface and morphological properties of the obtained composites were studied by Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) techniques. Thermal properties of these Cu-POM-PU composites were determined by thermogravimetric analysis, differential thermal analysis and differential scanning calorimetry analysis techniques. Dielectric properties of the Cu-POM-PU composites were also determined. The dielectric measured results showed that the dielectric constants decreased with the increase of the Cu-POMs content. The Cu-POM-PU composites showed relatively low dielectric constant compared to pure PUs.

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The aim of this study is to synthesize activated carbon with high surface area from peach kernel shells which is an agricultural waste. In this study, activated carbon synthesis was carried out by using CO 2 at 2 different temperatures (800 and 900 °C) with physical activation from products carbonized at 4 different temperatures (300, 400, 500, and 600 °C) and 2 different N2 gas flow rates (100 and 500 mL/min). After carbonization, solid, liquid, and gas yields of the materials were calculated. The surface area of activated carbons synthesized was calculated by BET analysis and the differences in the surface area were shown by changing the synthesis conditions. Surface areas vary between 340.15 and 686.74 m 2 /g. In samples pores formed were examined by DFT plus. It was found that most of these pores consist of micropores. Also, the structures of the samples were examined with SEM and XRD analyses. Methylene blue removal of the synthesized samples was studied and the results were compared.