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A new β and <I>N</I>-substituted pyrrole, <I>N</I>-trimethylsilylethoxymethyl-3-methyl-4-pyrrole carboxylate ethyl ester (MPCE-SEM) is synthesised and copolymerised electrochemically with unsubstituted pyrrole to gives free-standing films for conductivity measurements. The electrochemical polymerisation of MPCE-SEM gives only soluble dimers and oligomers rather than polymers because the steric constraints stabilise the oligomeric cation radical of MPCE-SEM. The thiophene monomers containing mesogenic group at the 3-position via an alkyl chain are synthesised and polymerised chemically to give insoluble, infusible polymers and do not exhibit liquid crystalline behaviour. The conductivities of pressed-pellets of the polymer powders are lower than 10<SUP>-5</SUP>S/cm. The electrochemical polymerisation of the thiophene monomers containing mesogenic group of 4-methoxyazbenzen-4'-yloxy or 4-butylazobenzen-4'-yloxy in dichloromethane solution gives a low yield of polymers, which is accompanied by the formation of soluble dimers and oligomers as well as degradation of the resulting polymer and the mesogenic group. Poly{<I>N </I>-11-[(4-cyanobiphenyl-4'-yloxy) undecyl] pyrrole} obtained from chemical polymerisation of the corresponding monomer shows high molecule weight, is soluble in common solvents and fusible showing smectic A liquid crystalline behaviour. This polymer in the melt (175<SUP>o</SUP>C) has a conductivity of 6.6 x 10<SUP>-15 </SUP>S/cm. X-ray photoelectron spectrometry analysis on the melt processed film gives an estimated doping level of an anion every 6-7 monomer units. Electrochemical oxidation of the <I>N</I>-substituted pyrrole monomers gives the electroactive conjugated free-standing polymer films. The conductivities of the free standing polymer films are lower than 10<SUP>-4</SUP> S/cm. A conducting copolymer containing a side chain liquid crystalline group, poly{<I>N</I>-8-[(4-cyanobiphenyl-4'-yloxy)octyl]-2,5-di(2-thienyl) pyrrole} can be obtained electrochemically from the corresponding monomer. The polymer is slightly soluble in chloroform giving a dark green solution but is not liquid crystalline.

This thesis reports the development of sonoelectrochemistry as a technique for sample analysis. Complementary modelling gives an insight into the mass transport and electrode reaction mechanisms. Separate studies were conducted as follows: - Initially an copper(II) acetate buffer system was used as its speciation can be determined. In order to establish under which conditions analysis could be conducted the effect of speciation was examined. These were applied to the Anodic Stripping Voltammetry (ASV) determination of copper in the acetate solution and to facilitate the use of a traditionally inhospitable electrochemical medium: real ale with minimal pre-treatment. Both gave detection limits of the range (1-100) μg L^-1 and in quantitative agreement with Atomic Absorption Spectroscopy. - The effect of acoustic streaming under mild insonation was studied by modelling Square Wave Voltammetry (SWV) of ASV and was found, when compared to experiment, to be the dominating factor. When the latter is strongly present two distinct mass.transport regimes were identified. Studies of chemical and electrochemical processes suggested that the acoustic streaming model fails under more extreme conditions. - SWV voltammetry was modelled for reversible electrochemical reactions leading to a refinement of existing analytical theory and the ASV modelling extended to account for surface morphology and finite electrode kinetics. Droplets on an electrode surface subjected to a potential sweep give rise to voltammetric traces attributed to charge insertion. Three mechanisms for this are proposed: (i) charge injection at the droplets surface, (ii) charge injection at the three phase boundary and (iii) the droplet is saturated with counter ions and electron transfer occurs at the electrode surface. These are solved numerically and incorporate Regular Solution Theory to account for non-ideal interactions. Comparing with experimental data an approximate model identified the processes occurring for small droplets. A Marangoni-type convection is suggested for larger droplets.

Thesis (PhD)--University of South Australia, 1995

Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1915. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed April 24, 2009) Includes bibliographical references (p. 15).

Thesis (Ph. D.)--University of Pennsylvania, 1904. / Includes bibliographical references.

Thesis (Ph. D.)--Vanderbilt University, 1933. / Bibliography: p. 48-49.