Metal polymer composite nanofiber production by electrospinning

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2009
Karakoç, Nihan
This study aims synthesis of metal/polymer one dimensional nanostructures by micelle formation, reduction, and electrospinning route, and to analyze the morphological characteristics of composite nanofibers. The study was carried out in three main steps. First, the reverse micelle structures were established between the anionic surfactant and the metal ion. The surfactant acts as an agent to bind metal ions together so that the arrangements of metal ions can be controlled in the solution. As the surfactant concentration increases, reverse micelles grow and reverse wormlike micelle structures are observed. Wormlike micelles are elongated semi flexible aggregates which form a spherocylinder form repeating units. Metal ions are in the core and surrounded with the surfactant. The polymer attached to the wormlike structure acts as a shield and prevents phase separation in a hydrophilic medium. Different polymer and surfactant concentrations were tried to determine the optimum polymer and surfactant concentrations for reverse micelle formation. The size analyses of the reverse micelle structures were done by dynamic light scattering technique. In the second step, metal ions in the micelles were reduced by using hydrazine hydrate to obtain metal cores in the center of wormlike micelles. Finally, electrospinning was carried at room temperature and in air atmosphere. The characterization of nano composites was done by Scanning Electron Microscopy. It was found that the size of the reverse micelle structures affects the distribution of metal nano partices in polymer nano fibers. In order to distribute the metal nano particles homogeneously, the optimum size of reverse wormlike micelles was found to be between 420 and 450 nm.

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Citation Formats
N. Karakoç, “Metal polymer composite nanofiber production by electrospinning,” M.S. - Master of Science, Middle East Technical University, 2009.