Space charge and conduction measurements in gamma-irradiated polyethylene terephthalate

Nassiba Belkahla (1) , Nadia Saidi (1) , G. Teyssedre (2) , Laurent Berquez (2) , Sarah Mouaci (1) , Mohamed Saidi (1)

1 USTHB - Université des Sciences et de la Technologie Houari Boumediene = University of Sciences and Technology Houari Boumediene [Alger]
2 LAPLACE-DSF - Diélectriques Solides et Fiabilité

We report on the impact of irradiation on the dielectric properties of Poly(Ethylene Terephthalate)(PET).Thin films of PET were irradiated in air at room temperature by means of a 60 Co gamma source at a dose rate of approximately 31 Gy/min. Total doses of 30 kGy and 150 kGy were adopted in this work. The space charge profiles and residual electric field of virgin material and material exposed to these representative doses, obtained after 30 min of depolarization following field application in the range 40-200 kV/mm, have been examined by Laser-Intensity Modulation Method (LIMM). The dependence of space charge density with electric field values and irradiation dose is analysed. Under high DC voltages and after irradiation, the space charge stored in PET tends to be less than in reference PET. The charging and discharging currents tend to increase with the irradiation, considering both the transient contribution to the current and the conductivity contribution. Space charge and conduction measurements exhibit good agreement in the fact that higher conductivity would prevent charge accumulation.

Mots clés: Space charge; LIMM; gamma irradiation; PET; Space charge

Domaines: Matériaux

Nassiba Belkahla, Nadia Saidi, G. Teyssedre, Laurent Berquez, Sarah Mouaci, et al.. Space charge and conduction measurements in gamma-irradiated polyethylene terephthalate. 11e Conf. Société Française d'Electrostatique (SFE), Aug 2018, Grenoble, France. pp.1-5. ⟨hal-02397442⟩