ENTHALPY RELAXATION STUDIES IN AMORPHOUS POLY(ETHYLENE-TEREPHTHALATE)BY MODULATED DSC

Citation
Y. Wang et al., ENTHALPY RELAXATION STUDIES IN AMORPHOUS POLY(ETHYLENE-TEREPHTHALATE)BY MODULATED DSC, Journal of macromolecular science. Physics, B37(5), 1998, pp. 709-716
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Polymer Sciences
ISSN journal
0022-2348
Volume
B37
Issue
5
Year of publication
1998
Pages
709 - 716
Database
ISI
SICI code
0022-2348(1998)B37:5<709:ERSIAP>2.0.ZU;2-X
Abstract
Physical aging in amorphous poly(ethylene terephthalate) (PET) was stu died by means of modulated differential scanning calorimetry (MDSC). T wo different thermal histories were used: (1) quenching from above the T-g to 0 degrees C; (2) slow cooling at 1 degrees C/4 min from above the T-g to just below the T-g. The enthalpy relaxation of the amorphou s PET is affected by thermal histories induced by annealing below T-g. The data showed that all the parameters describing the relaxation pro cess (Delta H, T-max, and T-ons) were strongly dependent on the therma l histories of the sample before annealing. The magnitude and position of the endothermal peak are enhanced in the order slow cooling < quen ching.