Electrochemical synthesis of crowned conducting polymers : nature of radical cations in polymerization and mechanism of conductivity

Download

index.pdf

Date

2004

Author

Cihaner, Atilla

Metadata

Show full item record

Item Usage Stats

349
views

112
downloads

Poly(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 solvent and tetrabutylammonium tetrafluoroborate (TBABF4) or tetrabutylammonium hexafluorophosphate (TBAPF6) 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, Differential Scanning Calorimetry (DSC), and Thermogravimetric Analysis (TGA). Furthermore, new compounds consisting of bis(2-thienyl) methyl (I and II) and bis(2-thienyl) ethyl (III) 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 TBAPF6 dissolved in CH3CN. Also, I and II were polymerized via chemical oxidation which yielded broken ?-conjugated polymers except for III. The polymers were characterized using 1H-NMR and FT-IR spectroscopic techniques. In addition, copolymers of III with thiophene (Th) and pyrrole (Py) were studied with cyclic voltammetry (CV). SPEL behaviors of the products were investigated using UV-VIS spectroscopic technique.

Subject Keywords

Polymers.

URI

http://etd.lib.metu.edu.tr/upload/3/12605054/index.pdf
https://hdl.handle.net/11511/14234

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Electrochemical polymerization and characterization of polyether-substituted aniline derivatives Tirkeş, Süha; Oenal, Ahmet M. (Wiley, 2007-08-01) New compounds consisting of aniline units linked by polyether bridges have been synthesized and their electrochemical polymerization was performed via constant potential electrolysis and cyclic voltammetry in an aqueous solution containing 3.0 moI L-1 H2SO4. Chemical polymerization was carried out using (NH4)(2)S2O8 as oxidizing agent. It was found that both methods gave the same polymer product without any cleavage of the polyether bridge between aniline rings. The polymers were characterized using the Fou...
Pyrolysis mass spectrometric analysis of copolymer of polyacrylonitrile and polythiophene Oğuz, Gülcan; Hacaloğlu, Jale; Department of Polymer Science and Technology (2004) In the first part of this work, the structural and thermal characteristics of polyacrylonitrile, polyacrylonitrile films treated under the electrolysis conditions in the absence of thiophene, polythiophene and the mechanical mixture and a conducting copolymer of polyacrylonitrile/polythiophene have been studied by pyrolysis mass spectrometry technique. The thermal degradation of polyacrylonitrile occurs in three steps; evolution of HCN, monomer, low molecular weight oligomers due to random chain cleavages a...
Electroactive macromonomers based on pyrrole and thiophene: a versatile route to conducting block and graft polymers Yagci, Y; Toppare, Levent Kamil (Wiley, 2003-10-01) The synthesis of block and graft copolymers containing insulating and conducting polypyrrole or polythiophene segments via a two-step procedure is described. Synthetic pathways to prepare pyrrole and thiophene functional macromonomers involving conventional and controlled/living polymerizations such as anionic and cationic ring opening, atom transfer radical polymerization are discussed. The use of these macromonomers in subsequent electrochemical and chemical polymerizations, leading to the formation of co...
Electrochemical copolymerization of thiophene containing pseudo-polyether cages with pyrrole Cihaner, Atilla; Önal, Ahmet Muhtar (2006-01-01) Conducting copolymers were synthesized via the electrochemical oxidation of pyrrole (Py) in the presence of the monomer 1,12-bis(2-thienyl)-2,5,8,11-tetraoxadodecane (1). The presence of monomer I in the electrolytic solution greatly changed the CV behavior of Py during its potensiodynamic polymerization. The electroactivity of poly(I-co-Py) increased with the increasing amount of I in the comonomer mixture. Copolymer films were prepared via constant potential electrolysis in an electrolytic solution contai...
Synergistic effect of boron containing substances on flame retardancy and thermal stability of clay containing intumescent polypropylene nanoclay composites Dogan, Mehmet; Bayramlı, Erdal (Wiley, 2011-12-01) The functions of nanoclay and three different boron containing substances, zinc borate (ZnB), borophosphate (BPO(4)), and boron silicon containing preceramic oligomer (BSi), were studied to improve the flame retardancy of polypropylene (PP)-nanoclay-intumescent system composed of ammonium polyphosphate (APP) and pentaerythritol (PER). The flame retardancy of PP composites was investigated using limiting oxygen index (LOI), UL-94 standard, thermogravimetric analysis (TGA), and cone calorimeter.

Citation Formats

A. Cihaner, “Electrochemical synthesis of crowned conducting polymers : nature of radical cations in polymerization and mechanism of conductivity,” Ph.D. - Doctoral Program, Middle East Technical University, 2004.