| Publication Type |
Journal Article |
| Title |
Effect of physical aging on the Johari-Goldstein and alpha relaxations of D-sorbitol: A study by thermally stimulated depolarization currents |
| Authors |
J. J. Moura-Ramos H. P. Diogo Susana S. Pinto |
| Groups |
BioMol |
| Journal |
JOURNAL OF CHEMICAL PHYSICS |
| Year |
2007 |
| Month |
April |
| Volume |
126 |
| Number |
14 |
| Pages |
|
| Abstract |
The relaxations in amorphous D-sorbitol have been studied by thermally stimulated depolarization currents during annealing at 255 K, which is 17 K below its calorimetric glass transition temperature T-g=272 K. As the glass structurally relaxes on aging, the features of the alpha relaxation and of the Johari-Goldstein (JG) relaxation change with time. For the alpha relaxation (i) the dielectric strength decreases; (ii) the activation energy decreases; and (iii) the relaxation time increases. For the JG relaxation the dielectric strength also decreases but with a different time dependence, and there is no evidence for any modification of the kinetic features of the mobility. The amplitude of response to aging is higher for the higher temperature motional components of the Johari-Goldstein relaxation compared with the lower temperature ones. (c) 2007 American Institute of Physics. |
| DOI |
http://dx.doi.org/10.1063/1.2722263 |
| ISBN |
|
| Publisher |
AMER INST PHYSICS |
| Book Title |
|
| ISSN |
0021-9606 |
| EISSN |
|
| Conference Name |
|
| Bibtex ID |
ISI:000245691200031 |
| Observations |
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