Single and hybrid organoclay-filled PLA nanocomposites: mechanical properties, viscoelastic behavior and fracture toughening mechanism
Poly (lactic acid) (PLA) nanocomposites based on single and hybrid organic-modified montmorillonites were previously studied in terms of their morphologi-cal, thermal and fire performance. As surfactants of the organoclays influenced thecompatibility between the nanofillers and PLA with different de...
| Autores: | , , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2021 |
| País: | España |
| Institución: | Universitat Politècnica de Catalunya (UPC) |
| Repositorio: | UPCommons. Portal del coneixement obert de la UPC |
| Idioma: | inglés |
| OAI Identifier: | oai:upcommons.upc.edu:2117/343812 |
| Acceso en línea: | https://hdl.handle.net/2117/343812 https://dx.doi.org/10.1002/app.50784 |
| Access Level: | acceso abierto |
| Palabra clave: | Clay Composite materials Nanocomposites (Materials) Composites Mechanical properties Argila Materials compostos Nanocompòsits (Materials) Àrees temàtiques de la UPC::Enginyeria dels materials::Materials compostos |
| Sumario: | Poly (lactic acid) (PLA) nanocomposites based on single and hybrid organic-modified montmorillonites were previously studied in terms of their morphologi-cal, thermal and fire performance. As surfactants of the organoclays influenced thecompatibility between the nanofillers and PLA with different degrees of clay plate-lets dispersion, the present work investigated the effect of these features in themechanical properties of PLA nanocomposites. PLA nanocomposites specimenswere analyzed by dynamic-mechanical-thermal analysis, which pointed outchanges in the viscoelastic behavior of the materials by the incorporation of theorganoclays, namely the increase of the storage modulus due to polymerchains movements rest riction and reinfor cement effects associated with the disper-sion of the nanofillers. Flexural and impact testing showed that hybridorganomontmorillonites containing ester ammonium and ethoxylated amineimproved PLA's ductility, toughness and impact resistance. This behavior wasexplained by the high level of compatibility and interaction between the surfactantsand PLA chains due to the polar groups in their structures. These organoclays cau-sed a transition on PLA's fracture from brittle to ductile in a way that the toughen-ing mechanism was explained by crazing and multi-shear banding induced by theplasticized interfacial region around these organoclays |
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