Temperature dependent dielectric constant/loss investigations in annealed polyetherimide

International Conference on Materials Science and Technology 2012

Singh, R.^1 ; Kaushik, B.K.^2 ; Quamara, J.K.^2

Physics Department, SKIET, Kurukshetra

136118, India^1

Physics Department, NIT, Kurukshetra

136119, India^2

关键词: Annealed samples;    Dielectric behaviour;    Different frequency;    Dipolar relaxation;    Effect of annealing;    Ether linkages;    Temperature dependent;    Temperature regions;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/73/1/012109/pdf
DOI  :  10.1088/1757-899X/73/1/012109

来源: IOP

【 摘 要 】

Temperature dependent dielectric constant/loss behavior has been investigated for annealed Polyetherimide. For investigating the effect of annealing, the samples were kept at desired temperature (100°C) for a predetermined time (varying from 2-10 hrs). The samples were then cooled to room temperature and stored in a desicator. The dielectric constant/loss were measured in the temperature region varying from 30°-250°C using a precision LCZ meter, Keithley 3321 at different frequencies 120 Hz, 1 kHz, 10 kHz and 100 kHz. A significant decrease in dielectric constant Ε' in annealed samples below 120°C, is due to the suppression of dipolar relaxation process lying in this temperature region due to annealing. The enhancement in Ε' above 120°C, is due to the dominance of α-relaxation process. The dielectric behaviour of Polyetherimide in the temperature region below 120°C is mainly governed by the dipolar relaxation processes owing either to ether linkages or to >C=O groups. Annealing has resulted in a loss of dipolar relaxation processes which is further confirmed from the fact that Ε' varies scarcely with temperature.