Metal polymer composite nanofiber production by electrospinning

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.


Chiral seperations by enzyme enhanced ultrafiltration : fractionation ofracemic benzoin
Ölçeroğlu, Ayşe Hande; Yılmaz, Levent; Department of Chemical Engineering (2006)
In this study, a methodology for separation of chiral molecules, by using enhanced ultrafiltration system was developed. Benzoin was the model chiral molecule studied. In the scope of developing this methodology, some parameters were investigated in the preliminary ultrafiltration experiments in order to set the operation conditions for enhanced ultrafiltration experiments. Due to the slight solubility of benzoin in pure water, 15% (v/v) Polyethylene glycol (PEG 400) and 30 % (v/v) Dimethyl sulfoxide (DMSO)...
Synthesis of silver nanoparticles and cable like structures through coaxial electrospinning
Çınar, Simge; Gündüz, Güngör; Department of Chemical Engineering (2009)
The aim of this study is to demonstrate the possibility of production of nanocables as an alternative to the other one dimensional metal/polymer composite structures like nanowires and nanorods. There is no certain definition of nanocables; however they could be considered as assemblies of nanowires. Nanocable structure can be defined as a core-shell structure formed by a polymeric shell and a metal core that runs continuously within this shell. To produce nanocables, two main steps were carried out. Firstl...
Quantum chemical simulation of nitric oxide reduction by ammonia (scr reaction) on v2o5 / tio2 catalyst surface
Soyer, Sezen; Önal, Işıl; Department of Chemical Engineering (2005)
The reaction mechanism for the selective catalytic reduction (SCR) of nitric oxide by ammonia on (010) V2O5 surface represented by a V2O9H8 cluster was simulated by density functional theory (DFT) calculations. The computations indicated that SCR reaction consisted of three main parts. In the first part ammonia activation on Brønsted acidic V-OH site as NH4+ species by a nonactivated process takes place. The second part includes the interaction of NO with pre-adsorbed NH4 + species to eventually form nitros...
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Güner, Özge; Üner, Deniz; Department of Chemical Engineering (2007)
In this study, the surface acidity of Co and/or Pb doped SBA15 mesoporous catalysts were investigated by both diffuse reflectance fourier transform (DRIFT) infrared spectroscopy and transmission mode fourier transform infrared spectroscopy. Pyridine was used to identify the Brønsted and Lewis acid sites of the surface, at room temperature. From the DRIFT spectrum typical stretching vibrations of isolated terminal silanol (Si-OH) groups were observed for all the catalysts. These silanol group bands dissappea...
Numerical simulation of radiating flows
Karaismail, Ertan; Selçuk, Nevin; Department of Chemical Engineering (2005)
Predictive accuracy of the previously developed coupled code for the solution of the time-dependent Navier-Stokes equations in conjunction with the radiative transfer equation was first assessed by applying it to the prediction of thermally radiating, hydrodynamically developed laminar pipe flow for which the numerical solution had been reported in the literature. The effect of radiation on flow and temperature fields was demonstrated for different values of conduction to radiation ratio. It was found that ...
Citation Formats
N. Karakoç, “Metal polymer composite nanofiber production by electrospinning,” M.S. - Master of Science, Middle East Technical University, 2009.