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Article Citation - WoS: 6Citation - Scopus: 5Synthesis of a regular polymer containing pseudo-polyether cages(Elsevier Science Sa, 2005) Cihaner, A; Önal, AMA new compound consisting of 2-thienyl units linked by polyether bridge has been synthesized and its electrochemical polymerization was performed via constant potential electrolysis (CPE) in an electrolytic solution containing 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF(6)) dissolved in CH3CN. Chemical polymerization was carried out using FeCl3 as oxidizing agent. It is found that both methods gave the same polymer product without any cleavage of the polyether bridge between thiophene (Th) rings. Although as synthesized polymers exhibited no conductivity, they gain conductivity via chemical doping using 12 vapor exposure. The polymers were characterized using FTIR spectroscopic technique and 12 doping was monitored using in-situ electron spin resonance (ESR) spectroscopy. Thermal behavior of electrochemically prepared polymer was investigated using differential scanning calorimetry, DSC and thermogravimetric analysis, TGA. (c) 2005 Elsevier B.V. All rights reserved.Article Citation - WoS: 1Citation - Scopus: 1Spectroelectrochemical Investigation of the Anodic Oxidation of Dibenzo-18(Elsevier Science Sa, 2004) Cihaner, A; Önal, AMPoly(dibenzo-18-crown-6) (poly-DB18C6) was synthesized by electrochemical oxidation of dibenzo-18-crown-6 (DB18C6) using a mixture of acetonitrile and dichloromethane as the solvent and tetrabutylammonium tetrafluoroborate (TBABF(4)) or tetrabutylammonium hexafluorophosphate (TBAPF(6)) as supporting electrolyte. The anodic polymerization of DB18C6 was investigated using in situ ESR and in situ UV-Vis spectroscopic techniques. Spectroelectrochemical (SPEL), properties and thermal analysis of the resulting polymers have been investigated using UV-Vis spectroscopy, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). (C) 2004 Elsevier B.V. All rights reserved.Article Citation - WoS: 6Citation - Scopus: 6Synthesis and Polymerization of 2-And 3-Substituted Thiophene Derivatives Linked by Polyether Bridges(Elsevier Science Sa, 2004) Tirkes, S; Cihaner, A; Önal, AMNew compounds consisting of 2- and 3-thienyl units linked by polyether bridges have been synthesized and their electrochemical polymerization was performed via constant potential electrolysis (CPE) in an electrolytic solution containing 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF(6)) dissolved in CH3CN. 2-Thienyl monomers (I and II), but not 3-thienyl monomers (III and IV), were also polymerized via chemical oxidation, which yielded broken pi-conjugated polymer products. The polymers were characterized using H-1 NMR and FT-IR spectroscopic techniques. It was found that both chemical and electrochemical oxidation of 2-thienyl monomers gave mainly poly(2,2'-bithiophenemethylene) due to elimination of polyether chains during the polymerization reaction. On the other hand, electrochemical oxidation of 3-thienyl monomers resulted in corresponding polymers without any cleavage of polyether bridges. Spectroelectrochemical (SPEL) properties of the products were investigated using UV-Vis spectroscopic techniques. (C) 2004 Elsevier B.V. All rights reserved.Article Citation - WoS: 28Citation - Scopus: 31Electrochemical Polymerization of 9-Fluorenone(Elsevier Science Sa, 2004) Cihaner, A; Tirkes, S; Önal, AMElectrochemical polymerization of 9-fluorenone, FO, was studied in CH2Cl2 solution with tetrabutylammonium tetrafluoroborate, TBABF(4), as the electrolyte, via constant potential electrolysis, CPE. Prior to CPE, the redox behavior of FO was investigated in the same solvent/electrolytic medium using cyclic voltammetry, CV. CPE of FO yielded an insoluble polymer deposit on the electrode surface. The product was characterized by FTIR spectroscopy techniques. The redox and spectroelectrochernical, SPEL, behavior of the polymer were studied by CV and in situ UV-Vis spectrophotometric techniques at various potentials, respectively. The conductivity was measured using a two-probe technique and the paramagnetic behavior of the polymer was monitored using in situ ESR spectroscopy. (C) 2004 Elsevier B.V. All rights reserved.Article Citation - WoS: 40Citation - Scopus: 44Surface Characterization and Radical Decay Studies of Oxygen Plasma-Treated Pmma Films(Wiley, 2013) Ozgen, Ozge; Aksoy, Eda Ayse; Hasirci, Vasif; Hasirci, NesrinPolymethylmethacrylate (PMMA) films were modified by RF oxygen plasma with various powers applied for different periods, and the effects of these parameters on the surface properties such as hydrophilicity, surface free energy (SFE), chemistry, and topography were investigated by water contact angle, goniometer, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy, and the types of the created free radicals and their decay were detected by electron spin resonance spectroscopy (ESR). SFE and contact angle results varied depending on the plasma parameters. Oxygen plasma treatment (100 W-30 min) enhanced the hydrophilicity of PMMA surface as shown by decreasing the water contact angle from 70 degrees to 26 degrees. XPS analysis showed the change in the amounts of the present functionalities as well as formation of new groups as free carbonyl and carbonate groups. The roughness of the surface increased considerably from similar to 2 nm to similar to 75 nm after 100 W-30 min oxygen plasma treatment. ESR analysis indicated the introduction of peroxy radicals by oxygen plasma treatment, and the intensity of the radicals increased with increasing the applied power. Significant decrease in radical concentration was observed especially for the samples treated with higher powers when the samples were kept under the atmospheric conditions. As a conclusion, RF plasma, causes changes in the chemical and physical properties of the materials depending on the applied parameters, and can be used for the creation of specific groups or radicals to link or immobilize active molecules onto the surface of a material. Copyright (C) 2012 John Wiley & Sons, Ltd.
