by Kabtoul, B. and Ramos, M. A.
Abstract:
In this work, we present new calorimetric and thermodynamic measurements conducted on pure ethanol for its two kinds of glass transition, namely the conventional or structural glass transition and also the dynamical freezing of the plastic crystal (PC) state into an orientationally-disordered crystal (or glassy crystal), that are found to occur exactly at the same temperature (Tg ≈ 97 K) and with comparable discontinuities in the specific heat. We have studied the dependence of the corresponding fictive temperatures on the different cooling rates and/or thermal annealing processes followed. The apparent activation energy and the concomitant fragility index were thus calculated for each glassy phase of ethanol, finding that the PC is a stronger “glass former” than the supercooled liquid.
Reference:
Structural and enthalpy relaxation processes in pure ethanol (Kabtoul, B. and Ramos, M. A.), In physica status solidi (a), volume 208, 2011.
Bibtex Entry:
@article{kabtoul_structural_2011,
title = {Structural and enthalpy relaxation processes in pure ethanol},
volume = {208},
issn = {1862-6319},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/pssa.201000758},
doi = {10.1002/pssa.201000758},
abstract = {In this work, we present new calorimetric and thermodynamic measurements conducted on pure ethanol for its two kinds of glass transition, namely the conventional or structural glass transition and also the dynamical freezing of the plastic crystal (PC) state into an orientationally-disordered crystal (or glassy crystal), that are found to occur exactly at the same temperature (Tg ≈ 97 K) and with comparable discontinuities in the specific heat. We have studied the dependence of the corresponding fictive temperatures on the different cooling rates and/or thermal annealing processes followed. The apparent activation energy and the concomitant fragility index were thus calculated for each glassy phase of ethanol, finding that the PC is a stronger “glass former” than the supercooled liquid.},
language = {en},
number = {10},
urldate = {2021-07-13},
journal = {physica status solidi (a)},
author = {Kabtoul, B. and Ramos, M. A.},
year = {2011},
note = {No CMAM},
keywords = {ethanol, glass transition, specific heat, activation energy, annealing, configurational enthalpy, fictive temperature, orientationally-disordered crystal},
pages = {2249--2253},
file = {Full Text PDF:E:\Usuarios\Administrator\Zotero\storage\8LXJSI8P\Kabtoul y Ramos - 2011 - Structural and enthalpy relaxation processes in pu.pdf:application/pdf;Snapshot:E:\Usuarios\Administrator\Zotero\storage\4378C86P\pssa.html:text/html},
}