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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Novos poli(p-xilileno)s e poli(p-fenileno vinileno)s obtidos via quinodimetanos gerados catodicamente / Novel poly(p-xylylene) s and poly (p-phenylene vinylene) are obtained via cathodically generated quinodimethanes

Rosamaria Wu Chia Li 14 November 2002 (has links)
Esta tese envolveu a síntese de 11 precursores poliméricos inéditos, derivados de bifenilos e terfenilos, substituídos por grupos receptores e doadores de elétrons, por meio de reações de acoplamento de Suzuki. Tais precursores foram convertidos aos respectivos polímeros, poli(p-xilileno)s e poli(p-fenileno vinileno)s, via redução catódica, conduzindo a um total de 11 polímeros, sendo dez deles inéditos. Os polímeros obtidos foram caracterizados por métodos espectroscópicos (UV-VIS, IV, RMN), análises térmicas, SEC e medidas de condutividade elétrica pós-dopagem. Um dos polímeros foi empregado na construção de dispositivos metal/polímero/metal (\"sanduíche\"), que permitiram a determinação da mobilidade dos portadores de carga, bem como da altura de barreira para injeção de elétrons na junção metal/polímero. / The synthesis via Suzuki coupling reaction of 11 new biphenylenic and terphenylenic polymer precursors, substituted by long-chain electron donating or withdrawing groups, is described. The electrochemical reduction of these precursors led to the corresponding poly(p-xylylene)s and poly(p-phenylene vinylene)s. Ten out of the 11 generated polymers have been never described before. AII the polymers were fully characterised by spectroscopic (UV-VIS, IR, NMR) and thermal analyses, as well as by SEC and electrical conductivity measurements of iodine-doped specimens. The positive charge carrier mobility and the barrier height for electron injection (metal/polymer) could be determined through I x V investigations of sandwich devices (metal/polymer/metal) for one of the polymers.

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