Son yıllarda, grafen sahip olduğu üstün elektronik, termal ve mekanik özellikler nedeniyle bilim adamları ve sanayinin çok ilgisini çekmiş ve farklı alanlarda ve ileri uygulamalarda kullanılmaya başlanmıştır. Grafenin çok az miktarda katkı olarak kullanılması ile polimerlere ileri özellikler katması nedeniyle, grafen ve türevleri polimer kompozitler alanında da büyük ilgi uyandırmıştır. Bu nedenle, bu çalışmada, özellikle elektriksel iletkenlik ve mekanik özellikleri iyileştirilmiş epoksi kompozitler elde etmek için grafen belirli oranlarda (ağırlıkça %0,05, %0,1, %0,25, %0,5 ve %1) epoksi içerisine eklenmiş ve nanokompozit filmler üretilmiştir. Üretilen nanokompozitlerin özellikleri, fourier dönüşümlü kızılötesi spektroskopisi (FT-IR), termogravimetrik analiz (TGA), mekanik test, taramalı elektron mikroskobu (SEM), UV-Vis-NIR spektrofotometre ve elektriksel iletkenlik ölçümleri yapılarak incelenmiştir. Yapılan çalışma sonucunda, %1 oranında grafen katkısı, epoksi filmlerin hacimsel direnç değerinde %28,2 ve yüzeysel direncinde %9,7’lik bir azalmaya sebep olmuştur. Grafen/epoksi nanokompozitlerin maksimum gerilme değeri, %1’lik grafen katkısında, katkısız epoksiye göre %33,84 oranında artarak ~20 MPa olarak elde edilmiştir. Sonuç olarak, epoksiye ilave edilen grafen miktarı arttıkça, nanokompozit filmlerin elektriksel iletkenliğinin, gerilme değerlerinin ve ışık absorpsiyonunun arttığı gözlenmiştir. Elde edilen nanokompozit filmler, sağladığı iyileştirilmiş elektriksel iletkenlik ve mekanik özellikler sayesinde endüstriyel uygulamalarda kullanılabilir.
In recent years, graphene has attracted the attention of scientists and industry due to its superior electronic, thermal and mechanical properties and has been used in different fields and advanced applications. Graphene and its derivatives have also attracted great interest in the field of polymer composites, since the use of graphene as a small amount of additive brings about advanced properties to the polymers. Therefore, in this study, graphene was added to the epoxy at certain rates (0.05%, 0.1%, 0.25%, 0.5% and 1%) to obtain nanocomposites with improved electrical conductivity and mechanical properties. The properties of obtained nanocomposite films were examined by fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), mechanical test, scanning electron microscope (SEM), UV-Vis-NIR spectrophotometer and electrical conductivity measurements. 1% graphene additive caused a 28.2% decrease in the volumetric resistance and 9.7% in the surface resistance of the nanocomposite films. The maximum tensile value of graphene/epoxy nanocomposites was obtained as ~ 20 MPa by increasing 33.84% in 1% graphene additive compared to neat epoxy-based nanocomposites. As a result, it has been observed that as the amount of graphene added to the epoxy increases, the electrical conductivity, tensile values and light absorption of nanocomposite films increase. The nanocomposite films obtained can be used in industrial applications thanks to the improved electrical conductivity and mechanical properties.
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