| DOI | Trouver le DOI : https://doi.org/10.1021/am101260a |
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| Auteur | Rechercher : González-Domínguez, Jose M.; Rechercher : Ansón-Casaos, Alejandro.; Rechercher : Díez-Pascual, Ana M.; Rechercher : Ashrafi, Behnam1; Rechercher : Naffakh, Mohammed; Rechercher : Backman, David1; Rechercher : Stadler, Hartmut; Rechercher : Johnston, Andrew1; Rechercher : Gómez, Marian; Rechercher : Martínez, M. Teresa |
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| Affiliation | - Conseil national de recherches du Canada. Institut de recherche aérospatiale du CNRC
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| Format | Texte, Article |
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| Sujet | Detrimental effects; Dynamic mechanical behavior; Electrical percolation threshold; Epoxy nanocomposites; Atomic force microscopy; Block copolymers; Composite materials; Electric conductivity; Organic solvents; Single-walled carbon nanotubes (SWCN); Solvents; Tensile strength; Toughness; Impact strength |
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| Résumé | Multicomponent nanocomposite materials based on a high-performance epoxy system and single-walled carbon nanotubes (SWNTs) have been prepared. The noncovalent wrapping of nitric acid-treated SWNTs with a PEO-based amphiphilic block copolymer leads to a highly disaggregated filler with a boosted miscibility in the epoxy matrix, allowing its dispersion without organic solvents. Although direct dispersion of acid-treated SWNTs results in modestly improved epoxy matrix mechanical properties, the incorporation of wrapped SWNTs produces a huge increase in toughness (276% improvement at 0.5 wt % loading) and impact strength (193% at 0.5 wt % loading) with no detrimental effect on the elastic properties. A synergistic effect between SWNTs and the block copolymer is revealed on the basis of tensile and impact strength results. Atomic force microscopy has been applied, obtaining stiffness mappings that identify nanostructure features responsible of the dynamic mechanical behavior. The electrical percolation threshold is greatly reduced, from 0.31 to 0.03 wt % SWNTs when block copolymer-wrapped SWNTs are used, and all the measured conductivity values increased up to a maximum of 7 orders of magnitude with respect to the baseline matrix (1 wt % wrapped-SWNTs loading). This approach provides an efficient way to disperse barely dispersible SWNTs without solvents into an epoxy matrix, and to generate substantial improvements with small amounts of SWNTs. © 2011 American Chemical Society. |
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| Date de publication | 2011-04-15 |
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| Dans | |
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| Langue | anglais |
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| Publications évaluées par des pairs | Oui |
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| Numéro NPARC | 21272032 |
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| Exporter la notice | Exporter en format RIS |
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| Signaler une correction | Signaler une correction (s'ouvre dans un nouvel onglet) |
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| Identificateur de l’enregistrement | e4fb27f9-f427-4777-a879-7b99ec9a1482 |
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| Enregistrement créé | 2014-05-22 |
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| Enregistrement modifié | 2020-04-21 |
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