@article{6db6c22f58c143e1a1575cf6473c4387,
title = "Structural relaxation in gel-derived glasses",
abstract = "Glasses with the same composition and hydroxyl contents were prepared by conventional melting and by hydrolysis of alkoxides. The differential scanning calorimeter (DSC) was used to compare the kinetics of structural relaxation of the glasses. Detailed examination of the data shows that there is no difference between them after the gel has been sintered near the glass transition temperature. Changing the oxide content of the melted glass causes significant changes in the DSC plots, so it is very important to confirm (as was done in this study) that the gel and melted glasses are identical in composition.",
author = "Scherer, {George W.} and Brinker, {C. Jeffrey} and Roth, {E. Peter}",
note = "Funding Information: It has been reported that gel-derived glasses differ from conventionally melted glasses in properties such as devitrification products \[1\],v iscosity \[2,3\] and liquidus \[4\].T his is surprising, unless these glasses differ in composition, because structural rearrangements can occur in a matter of seconds at temperatures above the glass transition temperature, Tg. Therefore, significant structural differences between melted oxides and gel-derived glasses are not expected after the gel has been heated above Tg. The purpose of this study was to examine gels that had been sintered near T~ to see whether they differed from a melted oxide of the same composition. Great care was taken to insure that the oxide content and hydroxyl concentration were the same in both glasses. As in a previous study \[5\],w e used a differential scanning calorimeter (DSC) to examine the kinetics of tho relaxation of the enthalpy. The present data are more accurate than in the previous study, and the glasses are much closer in composition, but the conclusion is the same: no significant differences exist after the gel has been sintered near Tg, * This work was performed at Sandia National Laboratories supported by the US Department of Energy under contract number DE-AC04-76DP00789. ** Present address: E.I. du Pont de Nemours & Co., Central R&D Department, Experimental Station, Wilmington, DE 19898, USA.",
year = "1986",
month = jun,
day = "1",
doi = "10.1016/0022-3093(86)90130-4",
language = "English (US)",
volume = "82",
pages = "191--197",
journal = "Journal of Non-Crystalline Solids",
issn = "0022-3093",
publisher = "Elsevier B.V.",
number = "1-3",
}