Strain-induced crystallization of natural rubber and cross-link densities heterogeneities
Strain-induced crystallization (SIC) of natural rubber (NR) is characterized during a cyclic deformation at room temperature and low strain rate (~10–3 s–1) using in situ wide angle X-rays scattering (WAXS) measurements. The crystallinity index (CI) and average size of the crystallites in the three...
| Autores: | , , , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2014 |
| 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:2117/373768 |
| Acceso en línea: | https://hdl.handle.net/2117/373768 https://dx.doi.org/10.1021/ma5006843 |
| Access Level: | acceso abierto |
| Palabra clave: | Rubber Crystallization Strain induced crystallization Natural rubber In-situ WAXS Network heterogeneities Cautxú Cristal·lització Àrees temàtiques de la UPC::Enginyeria dels materials |
| Sumario: | Strain-induced crystallization (SIC) of natural rubber (NR) is characterized during a cyclic deformation at room temperature and low strain rate (~10–3 s–1) using in situ wide angle X-rays scattering (WAXS) measurements. The crystallinity index (CI) and average size of the crystallites in the three main directions are measured during loading and unloading. A scenario describing SIC is then proposed, assuming that SIC corresponds to the successive appearance of crystallite populations whose nucleation and growth depend on the local network density. From this scenario, a methodology, coupling experimental observations and thermodynamic description is developed to determine the distribution of the network chain density associated with the size of a corresponding crystallite population. Finally, complex cyclic tests are performed. They suggest the existence of a memory effect in the chains involved in crystallization, which eases the nucleation process of the crystallites. |
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