Utilize este identificador para referenciar este registo:
https://hdl.handle.net/1822/5488
Título: | Study of sol-gel derived di-ureasils doped with zinc triflate |
Autor(es): | Nunes, Sílvia Zea Bermudez, V. de Silva, Maria Manuela Smith, Michael John Morales, Enrique Ferreira, R. A. Sá Carlos, Luís Rocha, João |
Palavras-chave: | Ionic conductivity POE/siloxane Di-ureasils Zinc triflate |
Data: | 1-Set-2006 |
Editora: | Elsevier Science BV |
Revista: | Solid State Sciences |
Resumo(s): | Zinc triflate (Zn(CF3SO3)2)-doped sol-gel derived di-urea cross-linked POE/siloxane ormolytes (designated as di-ureasils) with ∞ > n ≥ 1 (where the salt content is expressed as n, the molar ratio of oxyethylene moieties to Zn2+ ions) were investigated. The hybrids with n ≥ 5 are entirely amorphous; those with n > 10 are thermally stable up to approximately 305 ºC. The siliceous network of representative samples (n = 200 and 10) is essentially composed of (SiO)3Si(CH2)- environments and is thus highly branched. The distance between the structural units in samples with 200 ≥ n ≥ 10 and n ≤ 7 is 4.2 and 4.3 Å, respectively. The estimated interdomain distance is 11 and 13 Å for xerogels with 200 ≥ n ≥ 20 and n ≤ 10, respectively. At n = 1 a crystalline POE/Zn(CF3SO3)2 complex of unknown stoichiometry is formed. The conductivity maxima are located at n = 60 (3x10-6 S cm-1) and n = 20 (7x10-5 S cm-1) at 30 and 100 ºC, respectively. |
Tipo: | Artigo |
Descrição: | Prova tipográfica (In Press) A publicar em "Solid States Sciences". |
URI: | https://hdl.handle.net/1822/5488 |
DOI: | 10.1016/j.solidstatesciences.2006.07.013 |
ISSN: | 1293-2558 |
Acesso: | Acesso aberto |
Aparece nas coleções: | CDQuim - Artigos (Papers) |
Ficheiros deste registo:
Ficheiro | Descrição | Tamanho | Formato | |
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newSSScZn.pdf | main article with figures and tables | 1,64 MB | Adobe PDF | Ver/Abrir |