OATAO - Open Archive Toulouse Archive Ouverte Open Access Week

Electrical conductivity of a silicone network upon electron irradiation: influence of formulation

Roggero, Aurélien and Dantras, Eric and Paulmier, Thierry and Tonon, Claire and Lewandowski, Simon and Dagras, Sabine and Payan, Denis Electrical conductivity of a silicone network upon electron irradiation: influence of formulation. (2016) Journal of Physics D: Applied Physics, 49 (50). 505303. ISSN 0022-3727

[img]
Preview
(Document in English)

PDF (Author's version) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
1MB

Official URL: http://dx.doi.org/10.1088/0022-3727/49/50/505303

Abstract

In this study, the electrical conductivity of a silicone elastomer filled with inorganic fillers was investigated upon electron irradiation. Neat samples consisting of the isolated polysiloxane matrix (with no fillers) were studied in parallel to identify the filler contribution to this evolution. It was shown that exposure to 400 keV electron doses induced a decrease in electrical conductivity for both the filled and neat materials. This decrease was much more pronounced with the filled samples than with the neat ones. Moreover, the activation energy of electrical conductivity (Arrhenius behaviour) doubled in the filled case, while it varied only weakly for the neat case. In light of these results, structure–property relationships were proposed on the basis of the radiation-induced crosslink processes to which this material is subject. In the framework of electronic percolation theory, it is suggested that the radiation-induced formation of SiO3 crosslinks in the polysiloxane network and SiO4 crosslinks at filler–matrix interfaces affects the percolation path of the material, which can be simply modelled by a network of resistors in series. On one hand, their densification increases the overall resistance of the percolation path, which results in the observed decrease of effective electrical conductivity. On the other hand, the steep increase in activation energy in the filled material attributes to the SiO4 crosslinks becoming the most restrictive barrier along the percolation path. In spite of the misleading likeness of electrical conductivities in the pristine state, this study presented evidence that silicone formulation can affect the evolution of electrical properties in radiative environments. To illustrate this conclusion, the use of this material in space applications, especially when directly exposed to the radiative space environment, was discussed. The decrease in electrical conductivity was associated with a progressively increasing risk for the occurrence of electrostatic discharge and consequent spacecraft failures.

Item Type:Article
Additional Information:Thanks to Institute of Physics editor. The definitive version is available at http://iopscience.iop.org/
Audience (journal):International peer-reviewed journal
Uncontrolled Keywords:
Institution:Other partners > Airbus (FRANCE)
French research institutions > Centre National d'Études Spatiales - CNES (FRANCE)
French research institutions > Centre National de la Recherche Scientifique - CNRS (FRANCE)
Université de Toulouse > Institut National Polytechnique de Toulouse - INPT (FRANCE)
French research institutions > Office National d'Etudes et Recherches Aérospatiales - ONERA (FRANCE)
Université de Toulouse > Université Toulouse III - Paul Sabatier - UPS (FRANCE)
Laboratory name:
Statistics:download
Deposited By: cirimat webmestre
Deposited On:16 Dec 2016 15:19

Repository Staff Only: item control page