| Texto completo | |
| Autor(es): |
Franco, Roberto W. A.
[1]
;
Brasil, Carlos A.
[1]
;
Mantovani, Gerson L.
[1]
;
de Azevedo, Eduardo R.
[1]
;
Bonagamba, Tito J.
[1]
Número total de Autores: 5
|
| Afiliação do(s) autor(es): | [1] Univ Sao Paulo, Sao Carlos Inst Phys, BR-13560970 Sao Carlos, SP - Brazil
Número total de Afiliações: 1
|
| Tipo de documento: | Artigo Científico |
| Fonte: | MATERIALS; v. 6, n. 1, p. 47-64, JAN 2013. |
| Citações Web of Science: | 4 |
| Resumo | |
In this study, Cross-Polarization Magic-angle Spinning CP/MAS, 2D Exchange, Centerband-Only Detection of Exchange (CODEX), and Separated-Local-Field (SLF) NMR experiments were used to study the molecular dynamics of poly(ethylene glycol) (PEG) inside Hectorite/PEG intercalation compounds in both single-and double-layer configurations. The results revealed that the overall amplitude of the motions of the PEG chain in the single-layer configuration is considerably smaller than that observed for the double-layer intercalation compound. This result indicates that the effect of having the polymer chain interacting with both clay platelets is to produce a substantial decrease in the motional amplitudes of those chains. The presence of these dynamically restricted segments might be explained by the presence of anchoring points between the clay platelets and the PEG oxygen atoms, which was induced by the Na+ cations. By comparing the PEG motional amplitudes of the double-layered nanocomposites composed of polymers with different molecular weights, a decrease in the motional amplitude for the smaller PEG chain was observed, which might also be understood using the presence of anchoring points. (AU) | |
| Processo FAPESP: | 09/18354-8 - Dinâmica e estrutura de sistemas poliméricos estudados por ressonância magnética nuclear |
| Beneficiário: | Eduardo Ribeiro de Azevedo |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 04/07606-2 - Estudo da dinâmica molecular em compostos de intercalação através de ressonância magnética nuclear |
| Beneficiário: | Carlos Alexandre Brasil |
| Modalidade de apoio: | Bolsas no Brasil - Iniciação Científica |
| Processo FAPESP: | 09/54880-6 - Manipulação de spins nucleares através de técnicas de ressonância magnética e quadrupolar nuclear |
| Beneficiário: | Tito José Bonagamba |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |