INTEMA   05428
INSTITUTO DE INVESTIGACIONES EN CIENCIA Y TECNOLOGIA DE MATERIALES
Unidad Ejecutora - UE
artículos
Título:
Dynamics of transient metastable states in mixtures under coupled phase ordering and chemical demixing
Autor/es:
EZEQUIEL R. SOULÉ; ALEJANDRO D. REY
Revista:
EUROPEAN JOURNAL OF PHYSICS
Editorial:
IOP PUBLISHING LTD
Referencias:
Año: 2011 vol. 83 p. 357 - 367
ISSN:
0143-0807
Resumen:
We present theory and simulation of simultaneous chemical demixing and phase ordering in a polymer-liquid crystal mixture in conditions where isotropic-isotropic phase separation is metastable with respect to isotropic-nematic phase transition. In the case the mechanism is nucleation and growth, it is found that mesophase growth proceeds by a transient metastable phase that surround the ordered phase, and whose lifetime is a function of the ratio of diffusional to orientational mobilities. In the case of spinodal decomposition, different dynamic regimes are observed depending on the mobility ratio: metastable phase separation preceding phase ordering, phase ordering preceding phase separation, or simultaneous phase ordering and phase separation. Not only the overall dynamics but also the final structure of the material can be different for each kinetic regime.