Aging effects in poly(DTH succinate) observed with thermal-stimulated polarization and depolarization experiments

✍ Scribed by N. Suárez; M. Puma

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 180 KB
• Volume: 69
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19980711)69:2<293::aid-app10>3.0.co;2-y

✦ Synopsis

Thermal-stimulated polarization and depolarization experiments with blocking electrodes are performed on a particular tyrosine-derived polyarylate: poly(DTH succinate). Aging effects on this sample are observed for the glass transition relaxation peak and the charge redistribution peak originated by the conduction though the sample when blocking electrodes are present. The high temperature region where these peaks are present is modeled, and results are presented as a function of aging time. The model describes the experimental data to better than 1% for all the aging times. Contributions between the two peaks modeled are found to be constant and independent of aging. The glass transition temperature is constant within a fraction of a degree, and the shift of the maximum temperature of the spectrum is due to the charge redistribution peak. The results obtained suggest that the variation in shape of these peaks is originated by the change in the mobility of the polymeric chains, affecting in different manners the dipole orientation mechanism, as well as conduction through the sample. A simple logarithmic aging time dependence is found for most of the parameters used in the model.