Thesis (Ph.D.)--University of Wollongong, 2007. / Typescript. Includes bibliographical references.

Thesis (Ph.D.)--University of Wollongong, 2007. / Typescript. Includes bibliographical references.

Thesis (Ph. D.)--University of Akron, Dept. of Chemistry, 2008. / "December, 2008." Title from electronic dissertation title page (viewed 12/30/2008). Advisor, Matthew Espe; Committee members, Peter Rinaldi, James Hardy, Claire Tessier, Jutta Luettmer-Strathmann; Department Chair, Kim Calvo; Dean of the College, Ronald F. Levant; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.

Thesis (M.S.)--Missouri University of Science and Technology, 2010. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed January 6, 2010) Includes bibliographical references.

Thesis (M. Phil.)--University of Hong Kong, 2009. / Includes bibliographical references. Also available in print.

Thesis (Ph.D.) - University of St Andrews, September 2007. / Restricted until 14th September 2009.

Thesis (M.Sc.)--Memorial University of Newfoundland, 2004. / Bibliography: leaves 102-112.

Thesis (M.S.)--Rochester Institute of Technology, 2005. / Typescript. Includes bibliographical references (leaves 89-94).

Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xv, 192 p.; also includes graphics (some col.). Includes bibliographical references (p. 183-192). Available online via OhioLINK's ETD Center

Orientador: Younés Messaddeq / Coorientador: Agnieszka Joanna Pawlicka Maule / Banca: Caio Eduardo de Campos Tambelli / Banca: Rogéria Rocha Gonçalves / Resumo: Esta dissertação apresenta a preparação e caracterização de membranas condutoras iônicas baseadas em celulose produzida pela bactéria Gluconacetobacter xylinus. Estas membranas foram preparadas a partir da imersão de membranas de celulose bacteriana (CB) em soluções aquosas de ácidos (ácido acético e ácido trifluoroacético) e/ou plastificantes (trietanolamina e glicerol). Estrutura e perfil térmico destas membranas condutoras foram investigados por difração de raios X (DRX), microscopia eletrônica de varredura (MEV), termogravimetria (TG), calorimetria exploratória diferencial (DSC), espectroscopia vibracional na região do infravermelho (FTIR) e espectroscopia de espalhamento Raman. As propriedades elétricas foram avaliadas utilizando-se espectroscopia de impedância eletroquímica (EIE). As análises de DRX mostram o aumento de plastificante diminui a cristalinidade das amostras, cujo recobrimento das microfibrilas pelo plastificante pode ser visualizado por análise de MEV, e os valores de condutividade iônica obtidos são maiores em comparação aos da CB seca. A condutividade na membrana é dependente do conteúdo de umidade e o plastificante age impedindo a desidratação da membrana. Foi observado também que combinações de ácido e plastificante resultaram em membranas com maiores condutividades do que aquelas em que houve apenas adição do plastificante, uma vez que a adição de ácidos pode aumentar a condutividade protônica / Abstract: This dissertation presents the preparation and characterization of ionic conducting membranes based on cellulose produced by bacteria Gluconacetobacter xylinus. These membranes have been prepared from bacterial cellulose membranes (BC) soaked in acids (acetic and trifluoroacetic acids) and/or plasticizer (triethanolamine and glycerol) aqueous solutions. The structure and thermal behavior of the conducting membranes were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry (TG), differential scanning calorymetry (DSC), infrared spectroscopy (FTIR) and Raman spectroscopy. Electrical properties were performed utilizing electrochemical impedance spectroscopy (EIS). From XRD analyses the amorphous phase becomes larger after increasing the amount of plasticizer that covers the cellulose microfibrils as revealed by SEM, and the obtained conductivity values were high in comparison to dried BC. The conductivity in the membrane is dependent on the moisture content and the plasticizer acts avoiding complete membrane dryness. It was also observed that the combination of acid and plasticizer resulted in membranes with higher ionic conductivity than plasticized ones, once the addition of acids may improve protonic conductivity / Mestre