Mixtures of methyltetrahydrofuran (MTHF) with tristyrene and high molecular weight polystyrene involve an exceptionally large difference in the glass transition temperatures of the two components not realized in other binary mixtures studied before. The extensive study of the molecular dynamics of these mixtures by various experimental techniques by Blochowicz et al. has revealed the presence of a new Α'-relaxation not found before in other mixtures and also the more familiar Α- and Β-relaxations, but their properties are more extreme. Attention was focused on the new Α'-relaxation by Blochowicz et al. in interpreting it to originate from MTHF in confinement and explaining its properties by the Mode Coupling Theory. In a different direction, we concentrate on the highly unusual properties of the Α- and Β-relaxations. Earlier, we had success in explaining the properties of these two relaxations and their connection in other mixtures by the coupling model. In this paper, we apply the same model to explain the highly unusual dynamics of the Α- and Β-relaxations found in the mixtures of MTHF with tristyrene and polystyrene. Possible relation between the Α'- and the Β-relaxations also is explored.
Reconsidering the Dynamics in Mixtures of Methyltetrahydrofuran with Tristyrene and Polystyrene
CAPACCIOLI, SIMONE
2015-01-01
Abstract
Mixtures of methyltetrahydrofuran (MTHF) with tristyrene and high molecular weight polystyrene involve an exceptionally large difference in the glass transition temperatures of the two components not realized in other binary mixtures studied before. The extensive study of the molecular dynamics of these mixtures by various experimental techniques by Blochowicz et al. has revealed the presence of a new Α'-relaxation not found before in other mixtures and also the more familiar Α- and Β-relaxations, but their properties are more extreme. Attention was focused on the new Α'-relaxation by Blochowicz et al. in interpreting it to originate from MTHF in confinement and explaining its properties by the Mode Coupling Theory. In a different direction, we concentrate on the highly unusual properties of the Α- and Β-relaxations. Earlier, we had success in explaining the properties of these two relaxations and their connection in other mixtures by the coupling model. In this paper, we apply the same model to explain the highly unusual dynamics of the Α- and Β-relaxations found in the mixtures of MTHF with tristyrene and polystyrene. Possible relation between the Α'- and the Β-relaxations also is explored.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
