Slow rheological mode in glycerol and glycerol-water mixtures

Abstract

Glycerol-water mixtures were studied at molar concentrations ranging from $x_{\text{gly}}=1$ (pure glycerol) to $x_{\text{gly}}=0.3$ using shear mechanical spectroscopy. We observed a low frequency mode in neat glycerol, similar to what is usually reported for monohydroxy alcohols. This mode has no dielectric counterpart and disappears with increased water concentration. We propose that the hydrogen-bonded network formed between glycerol molecules is responsible for the observed slow mode and that water acts as a plasticizer for the overall dynamics and as a lubricant softening the hydrogen-bonding contribution to the macroscopic viscosity of this binary system.

References in corpus (9)

• Direct experimental evidence of a growing length scale accompanying the glass transition
• Fifth-order susceptibility unveils growth of thermodynamic amorphous order in glass-formers
• Short-chain polymer rigidity due to the Debye process of monohydroxy alcohols
• Supramolecular structures in monohydroxy alcohols: Insights from shear-mechanical studies of a systematic series of octanol structural isomers
• Beta relaxation in the shear mechanics of equilibrium viscous liquids: Phenomenology and network modeling of the alpha-beta merging region
• Linking the dielectric Debye process in 2-ethyl-1-hexanol to its density fluctuations
• Model for the alpha and beta shear-mechanical properties of supercooled liquids and its comparison to squalane data
• High pressure specific heat spectroscopy reveals simple relaxation behavior of glass forming molecular liquid
• Thermalization Calorimetry: A simple method for investigating glass transition and crystallization of supercooled liquids

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• Intra- and Intermolecular Inhomogeneities in the Course of Glassy Densification of Polyalcohols
• Eshelby description of highly viscous flow -- half model, half theory
• Non-rotational mechanism of polarization in alcohols
• Piezo-Electric Shear Rheometry: Further developments in experimental implementation and data extraction
• Impulsive stimulated scatttering signal in supercooled liquids with Debye or Havriliak-Negami relaxation of the specific heat capacity and thermal expansion coefficient
• Competing Supramolecular Structures: Dielectric and Rheological Spectroscopy on Glycerol/Propanol Mixtures