This thesis describes recent progress in electrochemical preparation of several
conducting polymers. In particular, the synthesis and characterizations of pure
polyaniline, pure polypyrrole, polyaniline/polypyrrole and polypyrrole/polyaniline
copolymers and polyaniline-polypyrrole physical blends were studied. The focus
has included firstly synthesis of these electrically conductive polymers.
Secondly, thermal characteristics of electrochemically synthesized homopoly- mers,
copolymers and their physical blends were investigated by thermal gravi- metric
analysis (TGA), differential scanning calorimetry (DSC) and direct pyrol- ysis mass
spectrometry (DIP-MS) techniques. In general, TGA analysis showed three-step
thermal degradation. The first, at 100oC, was attributed to water, and unreacted
monomers. The second weight losses observed at around 150 oC was because of
evolution of water and/or acid. Finally, the removal of the dopant ion and low
molecular weight species from the matrix were observed for pure PANI and pure PPy
at 230 and 280 oC, respectively. PANI/PPy films and PPy/PANI films have
decomposition temperatures at 272oC because of the loss of the dopant ion. It was also observed that pure PPy was thermally more resistant than pure PANI.
Thirdly, thermal characteristics, and degradation products of electrochemi- cally
prepared PANI/PPy and PPy/PANI films in solutions containing variable dopant
(SO42& / #8722 / ) concentrations were analyzed and compared with pyrolysis mass spectrometry.
Similar to TGA study, there were three main thermal degradation steps namely,
evolution of low molecular weight species, dopant based products and degradation
products of polymers. The dopant concentration was monitored
to optimize the degradation behavior. Pyrolysis mass spectrometry data showed that the degree of degradation of the polymer already coated on the electrode
enhanced as the dopant concentration used in synthesis increased.
| Identifer | oai:union.ndltd.org:METU/oai:etd.lib.metu.edu.tr:http://etd.lib.metu.edu.tr/upload/12608167/index.pdf |
| Date | 01 February 2007 |
| Creators | Tezal, Feride |
| Contributors | Kucukyavuz, Zuhal |
| Publisher | METU |
| Source Sets | Middle East Technical Univ. |
| Language | English |
| Detected Language | English |
| Type | M.S. Thesis |
| Format | text/pdf |
| Rights | To liberate the content for public access |
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