Carbon nanofibers are promising materials for several applications including energy storage, absorption, water filtration, drug delivery, catalysis, and sensors. They have superior properties including high surface area to volume ratio, nanoscale diameter, adjustable porosity and pore size, good flexibility, high chemical stability and excellent thermal and mechanical properties. Due to its high carbon content and good mechanical properties, polyacrylonitrile is the most commonly used carbon nanofiber precursor. However, polyacrylonitrile is not only very expensive but also petroleum based polymer. Considering the global warming and increasing demand to green materials, it is vital to use more environmentally friendly materials and limit usage of organic solvents. Polyvinyl alcohol (PVA) is a non-toxic and water-soluble polymer with hydroxyl groups in polymer chain that can break easily. Polyvinyl alcohol can be used as a carbon nanofiber precursor. Polyvinylpyrrolidone (PVP) is also water-soluble polymer and PVP enhances particle distribution and carbon yield when used as a carbon nanofiber precursor. In this study, PVA and PVP fibers were dissolved in water and they were produced via fast and safe nanofiber production technique. In this technique, high centrifugal force was applied to polymer solutions. After critical speed was reached, polymer jets were formed and under the influence of the force nanofibers were produced and colllected as nanofiber mats. The morphology of nanofibers were studied via SEM and thermal properties were studied with DSC.
Anahtar Kelimeler: PVP, PVA, nanofibers, water soluble
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