Título:
|
Structural transitions of nylon 47 and clay influence on its crystallization behavior
|
Autor/a:
|
Morales Gámez, Laura Teresa; Casas Becerra, María Teresa; Franco García, María Lourdes; Puiggalí Bellalta, Jordi
|
Otros autores:
|
Universitat Politècnica de Catalunya. Departament d'Enginyeria Química; Universitat Politècnica de Catalunya. PSEP - Polimers Sintètics: Estructura i Propietats. Polimers Biodegradables. |
Abstract:
|
Basic diffraction data on nylon 47 pointed out a peculiar structure of hydrogen bonds along
two directions. Nylon 47 showed reversible polymorphic transitions during heating/cooling
processes that were analyzed by real time synchrotron WAXD experiments. Results
indicated that nylon 47 had a first structural transition at low temperature, followed by
a gradual Brill transition towards a pseudohexagonal packing.
Nylon 47 crystallized from the melt giving rise to spherulites with different characteristics
than those attained with conventional even-even nylons. Interestingly, spherulites
crystallized at low supercooling underwent a reversible change in birefringence with temperature.
This was due to the reversible structural changes caused by temperature variations
and the flat on lamellar morphology.
Intercalated and exfoliated nanocomposites based on nylon 47 were prepared by solution
intercalation and melt mixing using Cloisites 25A and 30B. The influence of the final
silicate layer morphology on the hot crystallization behavior was investigated. Crystallization
rates of the neat polymer and its two nanocomposites were significantly different,
mainly due to variations in the primary nucleation |
Abstract:
|
Peer Reviewed |
Materia(s):
|
-Àrees temàtiques de la UPC::Enginyeria química -Polyamides -Polyamides -Brill transition -X-ray diffraction -Spherulitic morphology -Nanocomposites -Crystallization -Poliamides |
Derechos:
|
Attribution-NonCommercial-NoDerivs 3.0 Spain
http://creativecommons.org/licenses/by-nc-nd/3.0/es/ |
Tipo de documento:
|
Artículo - Versión publicada Artículo |
Compartir:
|
|