Evaluation of dielectric relaxation parameters from TSDC analysis of pristine and ion irradiated kapton-H polyimide

Sharma, Anjali; Yarramaneni, Sridharbabu; Quamara, J. K.

doi:10.1016/j.nimb.2011.02.008

Cited by 9 publications

(3 citation statements)

References 18 publications

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“…The distinguishing feature of the TSDC method is the low equivalent frequency, which is often used to extend dielectric measurements to the low frequency. The resulting global TSDC spectrum contains many peaks whose location, shape, and size provide valuable information on the timescale and dielectric strength of the different relaxation mechanisms that distinguish one material from another [12][13][14][15][16][17][18][19]. The result of the TSDC experiment is a global spectrum containing all the dielectric active relaxation processes excited by the electric field (Ep) between initial temperature (T0) and poling temperature (Tp).…”

Section: Introductionmentioning

confidence: 99%

TSDC of Irradiated and Non-Irradiated Cellulose Acetate

et al. 2021

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Films of cellulose acetate (CA) have been prepared by casting method using tetrahydrofuran (THF). CA films are γ-irradiated with varying radiation doses of 10, 20, 30, 40, 50 and 60 kGy using cobalt-60 ( 60 Co) source. Global thermally stimulated depolarization current (TSDC) of non-irradiated and irradiated CA samples has been investigated under the effect of various poling electric field (Ep) in a temperature range from 300 K to 440 K. It is observed that, global TSDC spectra of non-irradiated and irradiated CA samples are characterized by two relaxation peaks. One in the low temperature range ~321 K and the other in the high temperature range ~ 376-383 K are observed for non-irradiated sample. On the other hand, these temperatures are shifted towards lower temperature for irradiated samples to be located at 317 K and ~371 K. These relaxations are assigned as  and -relaxation and attributed to molecular motion of the polar acetate groups, C2H3O2 and polarization of the space charges, respectively. TStechnique has been carried out to decompose global TSDC spectra of all samples into its elementary peaks and the molecular parameters such as, activation energy and pre-exponential factor are calculated for each TS peak. Relaxation map (RM) of all samples has been analyzed using Eyring transformation and thermodynamic parameters such as, enthalpy activation (H), entropy activation (S) and Gibbs free energy (G) are estimated. The compensation phenomenon was verified by the linear relationship between both enthalpy and entropy.

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Section: Introductionmentioning

confidence: 99%

TSDC of Irradiated and Non-Irradiated Cellulose Acetate

et al. 2021

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“…While various material options were examined to attain the high-quality factor filters [10,25,26], it lacked scrutiny on the material attributes that enable the long-term charge retention. Moreover, the dielectric constant (ε r ) of material has rarely been associated with the charge decay phenomenon in experimental investigation [1,27], while there are implications that ε r is related with the charge stability and conductivity [7,27,28].The purpose of this work is to investigate the polymeric attributes that influence the charge retention capacity of electret filters. In this study, polymers with three different dielectric constants-polypropylene (PP), polyvinylidene fluoride (PVDF), and polyacrylonitrile (PAN)-were compared for their charge decay phenomena with varied aging conditions.…”

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confidence: 99%

Material Properties Influencing the Charge Decay of Electret Filters and their Impact on Filtration Performance

Lee

Kim

2020

Polymers

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Electret filters as opposed to mechanical filters display the enhanced ability to capture airborne particles with the electrostatic attraction. However, the environmental aging during shelf-life or use may cancel its benefit by dissipating the charges. This work investigates the polymeric attributes influencing the charge decay and the electrostatic filtration of electret filters, employing polymers with different dielectric constants (εr) and wettability. As accelerated aging, high temperature (120 °C) or high humidity (25 °C, 90% RH) was applied to the electret filters for 48 h. For the humidity aging, wetting property of material was a critical factor affecting the charge decay and the filtration performance, as the absorbed water increases the electrical conductivity. For the thermal aging, the material with the highest εr deteriorated the electric potential and the filtration performance by the largest extent, due to the lower band gap energy for charge transfer. The results of this study implicate that εr and wettability are important material parameters influencing the electric conductivity and chain mobility, and they can be used as convenient predictors for charge retention capacity affecting the robust electrostatic filtration performance.

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Review of the thermally stimulated depolarization current (TSDC) technique for characterizing dielectric materials

Song

Goud

et al. 2023

J. Korean Ceram. Soc.

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Evaluation of dielectric relaxation parameters from TSDC analysis of pristine and ion irradiated kapton-H polyimide

Cited by 9 publications

References 18 publications

TSDC of Irradiated and Non-Irradiated Cellulose Acetate

TSDC of Irradiated and Non-Irradiated Cellulose Acetate

Material Properties Influencing the Charge Decay of Electret Filters and their Impact on Filtration Performance

Review of the thermally stimulated depolarization current (TSDC) technique for characterizing dielectric materials

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