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The effects of elongation upon the structural and electronic properties of the conducting polymer polyaniline have been investigated. In particular, the properties of high molecular weight (ca. 150 000 Daltons) polyaniline have been examined, and the effects of increased molecular weight assessed. A method has been found to elongate the emeraldine base (EB) form up to 700% (l/l(_o)=8). This induces partial molecular alignment in the polymer which, upon doping, exhibits electrical conductivity of up to 700 Scm(_-1) and electrical anisotropy of almost 4.The mechanical properties of high molecular weight emeraldine base have been investigated as a function of elongation. The breaking stress has been observed to increase by almost one order of magnitude for a 500% elongated film compared with its unoriented counterpart. The breaking strain is found to decrease initially with increasing elongation, though no noticeable change is evident for samples elongated to more than 300%. Similarly, Young's modulus increases by a factor of 2 with increased elongation, but above 300% remains approximately constant. The behaviour has been interpreted in terms of the crystalline fraction of the samples. X-ray diffraction experiments have enabled the crystalline fraction of emeraldine base and emeraldine salt (ES) to be assessed. 300% elongated EB samples exhibit increased crystalhnity compared with as-cast samples. However, no further increase in crystallmity is evident for 600% elongated samples. Unoriented ES samples have a crystalline fraction of approximately 0.3. The crystallinity of 300% and 600% elongated ES samples is slightly less than for unoriented ES. The polarised reflectance spectra of EB and ES have been measured in the region 0.5- 5.6 eV. The results show increased optical anisotropy with increasing elongation for EB samples, but no change in anisotropy for ES samples above 300% elongation. A Kramers-Kronig analysis of the reflectance data reveals near metallic behaviour parallel to the dkection of elongation, and a high degree of localisation perpendicular to this direction.

Errata pasted on front end cover. / Bibliography: leaves 194-210. / xi, 210 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The aim of this study is to investigate the conductivity of pHEMA gel electrolytes and improve the understanding of the absorbed water in such hydrogels. The effect of the variation of the water content on conductivity is investigated in two ways ; the introduction of OED cross linkers yields hydrogels of reduced EWC through alteration of the nature of the polymer network and progressive dehydration enables a study of the conductivity with decreasing water content for individual copolymers. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physical and Inorganic Chemistry, 1996

Thesis (Master)--İzmir Institute of Technology, İzmir, 2005. / Keywords: Electrical conductivity, langmuir blodgett technique, metal soaps, nanofilms, moisture adsorption. Includes bibliographical references (leaves. 127-132).

Thesis (Ph. D.)--University of Illinois, 1913. / Biographical. "Reprinted from the Physical review, n.s., vol. II., no. 3, September, 1913."

Thesis (Ph. D.)--University of Wisconsin--Madison, 1928. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 76-80).

Thesis (Ph.D.)--University of California, Berkeley, 1961. / "UC-34 Physics" -t.p. "TID-4500 (16th Ed.)" -t.p. Includes bibliographical references (p. 67-68).

Thèse--Université de Paris. / At head of title: ... F. London. Published also as no. 458 in series Actualités scientifiques et industrielles. Translated by Edmond Bauer and J. Winter. "Rèfèrences": p. [79]-80. Includes bibliographical references.