TU Darmstadt / ULB / TUbiblio

Signature of a Type-A Glass Transition and Intrinsic Confinement Effects in a Binary Glass-Forming System

Blochowicz, T. and Schramm, S. and Lusceac, S. and Vogel, M. and Stühn, B. and Gutfreund, P. and Frick, B. (2012):
Signature of a Type-A Glass Transition and Intrinsic Confinement Effects in a Binary Glass-Forming System.
In: PHYSICAL REVIEW LETTERS, AMER PHYSICAL SOC, 109, (3), ISSN 0031-9007, [Online-Edition: http://dx.doi.org/10.1103/PhysRevLett.109.035702],
[Article]

Abstract

We study dynamically highly asymmetric binary mixtures comprised of small methyl tetrahydrofuran (MTHF) molecules and polystyrene. Combined use of dielectric spectroscopy, H-2 nuclear magnetic resonance, incoherent quasielastic neutron scattering, and depolarized dynamic light scattering allows us to selectively probe the dynamics of the components in a broad dynamic range. It turns out that the mixtures exhibit two glass transitions in a wide concentration range although being fully miscible on a macroscopic scale. In between both glass transition temperatures, the dynamics of the small molecules show strong confinement effects, e. g., a crossover from Vogel-Fulcher to Arrhenius behavior of the time constants. Moreover, the dynamical behavior of small molecules close to the slow matrix is consistent with mode coupling theory predictions for a type-A glass transition, which was expected from recent theoretical and simulation studies in comparable systems.

Item Type: Article
Erschienen: 2012
Creators: Blochowicz, T. and Schramm, S. and Lusceac, S. and Vogel, M. and Stühn, B. and Gutfreund, P. and Frick, B.
Title: Signature of a Type-A Glass Transition and Intrinsic Confinement Effects in a Binary Glass-Forming System
Language: English
Abstract:

We study dynamically highly asymmetric binary mixtures comprised of small methyl tetrahydrofuran (MTHF) molecules and polystyrene. Combined use of dielectric spectroscopy, H-2 nuclear magnetic resonance, incoherent quasielastic neutron scattering, and depolarized dynamic light scattering allows us to selectively probe the dynamics of the components in a broad dynamic range. It turns out that the mixtures exhibit two glass transitions in a wide concentration range although being fully miscible on a macroscopic scale. In between both glass transition temperatures, the dynamics of the small molecules show strong confinement effects, e. g., a crossover from Vogel-Fulcher to Arrhenius behavior of the time constants. Moreover, the dynamical behavior of small molecules close to the slow matrix is consistent with mode coupling theory predictions for a type-A glass transition, which was expected from recent theoretical and simulation studies in comparable systems.

Journal or Publication Title: PHYSICAL REVIEW LETTERS
Volume: 109
Number: 3
Place of Publication: ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
Publisher: AMER PHYSICAL SOC
Divisions: 05 Department of Physics > Institute for condensed matter physics > Experimental Condensed Matter Physics
05 Department of Physics > Institute for condensed matter physics
05 Department of Physics
Date Deposited: 20 Aug 2012 07:31
Official URL: http://dx.doi.org/10.1103/PhysRevLett.109.035702
Identification Number: doi:10.1103/PhysRevLett.109.035702
Related URLs:
Funders: Deutsche Forschungsgemeinschaft; FOR 1583, BL 923/1
Export:

Optionen (nur für Redakteure)

View Item View Item