English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/136480
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:

Influence of solvent on poly(2-(dimethylamino)ethyl methacrylate) dynamics in polymer-concentrated mixtures: a combined neutron scattering, dielectric spectroscopy and calorimetric study

AutorGoracci, Guido; Arbe, Arantxa ; Alegría, Ángel ; García Sakai, Victoria; Rudić, Svemir; Schneider, Gerald J.; Lohstroh, Wiebke; Juranyi, F.; Colmenero de León, Juan
Fecha de publicación2015
EditorAmerican Chemical Society
CitaciónMacromolecules 48(18): 6724-6735 (2015)
ResumenWe have investigated the dynamical processes-α-relaxation, local motions of the side-groups, and methyl group rotations-in poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) in the dry state and in mixtures (at 70 wt% polymer concentration) with tetrahydrofuran (THF) and water, to address the question as to how these polymer motions are affected by plasticizers interacting in different ways with the polymer. Differential scanning calorimetry, dielectric spectroscopy, and neutron scattering techniques on labeled samples (with deuterated solvents to isolate the signal of the polymer component) have been combined. The α-relaxation is drastically affected, with similar shifts of the glass-transition temperature for both solvents. Effects of compositional heterogeneities and reduction of the fragility are also observed. On the contrary, methyl-group dynamics are unaffected by the presence of solvent. Regarding side-group local motions (β-relaxation), two kinds of components-a slow and a fast one-could be identified in the dry state. On the basis of the spatial information provided by neutron scattering, a model for the geometry of the motions involved in the fast component has been proposed. Adding solvent, this process would remain essentially unaltered, but the population involved in the slower one would be reduced. With THF as solvent, this reduction would be complete, but with water it would be only partial. This could be attributed to rather heterogeneous distribution of water molecules in the polymer likely associated with the presence of water clusters. Such a scenario would also explain the much more pronounced broadening of the glass-transition region observed for the polymer in the aqueous mixture with respect to that induced by THF.
Versión del editorhttp://dx.doi.org/10.1021/acs.macromol.5b01316
Identificadoresdoi: 10.1021/acs.macromol.5b01316
e-issn: 1520-5835
issn: 0024-9297
Aparece en las colecciones: (CFM) Artículos
Ficheros en este ítem:
Fichero Descripción Tamaño Formato  
calorimetric study.pdf2,16 MBAdobe PDFVista previa
Mostrar el registro completo

Artículos relacionados:

NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.