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Title: Probing Toluene and Ethylbenzene Stable Glass Formation using Inert Gas Permeation

Abstract

Inert gas permeation is used to investigate the formation of stable glasses of toluene and ethylbenzene. The effect of deposition temperature (Tdep) on the kinetic stability of the vapor deposited glasses is determined using Kr desorption spectra from within sandwich layers of either toluene or ethylbenzene. The results for toluene show that the most stable glass is formed at Tdep = 0.92 Tg, although glasses with a kinetic stability within 50% of the most stable glass were found with deposition temperatures from 0.85 to 0.95 Tg. Similar results were found for ethylbenzene, which formed its most stable glass at 0.91 Tg and formed stable glasses from 0.81 to 0.96 Tg. These results are consistent with recent calorimetric studies and demonstrate that the inert gas permeation technique provides a direct method to observe the onset of molecular translation motion that accompanies the glass to supercooled liquid transition.

Authors:
; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1243270
Report Number(s):
PNNL-SA-111756
Journal ID: ISSN 1948-7185; 48154; KC0301050
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry Letters; Journal Volume: 6; Journal Issue: 18
Country of Publication:
United States
Language:
English
Subject:
Environmental Molecular Sciences Laboratory

Citation Formats

Smith, R. Scott, May, Robert A., and Kay, Bruce D. Probing Toluene and Ethylbenzene Stable Glass Formation using Inert Gas Permeation. United States: N. p., 2015. Web. doi:10.1021/acs.jpclett.5b01611.
Smith, R. Scott, May, Robert A., & Kay, Bruce D. Probing Toluene and Ethylbenzene Stable Glass Formation using Inert Gas Permeation. United States. doi:10.1021/acs.jpclett.5b01611.
Smith, R. Scott, May, Robert A., and Kay, Bruce D. 2015. "Probing Toluene and Ethylbenzene Stable Glass Formation using Inert Gas Permeation". United States. doi:10.1021/acs.jpclett.5b01611.
@article{osti_1243270,
title = {Probing Toluene and Ethylbenzene Stable Glass Formation using Inert Gas Permeation},
author = {Smith, R. Scott and May, Robert A. and Kay, Bruce D.},
abstractNote = {Inert gas permeation is used to investigate the formation of stable glasses of toluene and ethylbenzene. The effect of deposition temperature (Tdep) on the kinetic stability of the vapor deposited glasses is determined using Kr desorption spectra from within sandwich layers of either toluene or ethylbenzene. The results for toluene show that the most stable glass is formed at Tdep = 0.92 Tg, although glasses with a kinetic stability within 50% of the most stable glass were found with deposition temperatures from 0.85 to 0.95 Tg. Similar results were found for ethylbenzene, which formed its most stable glass at 0.91 Tg and formed stable glasses from 0.81 to 0.96 Tg. These results are consistent with recent calorimetric studies and demonstrate that the inert gas permeation technique provides a direct method to observe the onset of molecular translation motion that accompanies the glass to supercooled liquid transition.},
doi = {10.1021/acs.jpclett.5b01611},
journal = {Journal of Physical Chemistry Letters},
number = 18,
volume = 6,
place = {United States},
year = 2015,
month = 9
}
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