Skip to Main content Skip to Navigation
Theses

Etude des propriétés électriques des élastomères silicones utilisés pour l'isolation électrique

Abstract : The silicone rubbers are already largely used in the external electric insulation thanks to the good behaviour on the climatic constraints and the hydrophobicity. Silicone rubbers begin today to be used for high-voltage bulk insulation. The aim of this thesis was to more deeply analyze the dielectric and electric properties, little known, in these polymers.
The originality of these studies relates to the significant range of studied temperature (100-430K), the measurement of the dielectric responses in very low frequencies (10 -4 Hz-1MHz), the measurement of space charges by laser induced pressure pulse and measures it low currents (until 50fA). Two families of silicone rubbers were studied: RTV and LSR with silica fillers. These properties when materials are subjected to thermoelectric constraints (16 kV/mm with 353K) during one year are also carried out.
Behaviours classically observed in polymers were identified like the injection of space charges (Schottky effect). However, more specific behaviours were identified as :(i) sub-linear conduction currents, (ii) anomalous depolarization currents and chaotic response, (iii) fractional power law (FPR) on the dielectric response, (iv) low frequency dispersion (LFD) in the dielectric response after aging. These particular behaviours are mainly allotted of blocking electrode and conduction in the clusters located at the PDMS-silica interfaces.
The study in dielectric spectroscopy in the very low frequencies proved to be an invaluable tool for characterization of the whole of these phenomena.
Document type :
Theses
Complete list of metadata

Cited literature [133 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00011251
Contributor : Duc Hoang Nguyen <>
Submitted on : Thursday, December 22, 2005 - 11:21:06 AM
Last modification on : Wednesday, November 4, 2020 - 3:44:05 PM
Long-term archiving on: : Friday, November 25, 2016 - 9:59:08 AM

Identifiers

  • HAL Id : tel-00011251, version 2

Collections

Citation

Duc Hoang Nguyen. Etude des propriétés électriques des élastomères silicones utilisés pour l'isolation électrique. Energie électrique. Université Joseph-Fourier - Grenoble I, 2005. Français. ⟨tel-00011251v2⟩

Share

Metrics

Record views

1986

Files downloads

9559