Variable electrical properties in composites: Application to vanadium dioxide pigments in a polyethylene host

Journal Article · Sun May 01 00:00:00 EDT 1994 · Journal of Solid State Chemistry; (United States)

DOI:https://doi.org/10.1006/jssc.1994.1127· OSTI ID:6769129

Alfred-Duplan, C; Musso, J; Gavarri, J R; Cesari, C ^[1]

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1. Universite de Toulon et du Var, La Garde (France)

Composite pellets were prepared from low-density polyethylene (LDPE) and vanadium dioxide powders. The VO[sub 2] pigments are used for their insulating-to-metallic transition at 341 K in order to obtain electrically variable composite materials. The volume fractions of VO[sub 2] powders vary from [phi] = 0 to [phi] = 0.55. The composite samples are characterized by X-ray diffraction and scanning electron microscopy. Complex impedance analysis in the frequency range 10[sup [minus]1] to 10[sup 6]. Hz is carried out at room temperature and at T = 363 K, to observe the insulator-metal transition of VO[sub 2] pigments dispersed in the polymer host. The variation of the complex impedance modulus [vert bar]Z[vert bar] with frequency and with VO[sub 2] volume fraction ([phi]) is discussed. A specific (R, C) impedance model permits interpretation of the experimental results in terms of percolation; the observed variations can be accounted for.

• OSTI ID: 6769129
• Journal Information: Journal of Solid State Chemistry; (United States), Vol. 110:1; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
POLYETHYLENES
ELECTRIC IMPEDANCE
VANADIUM OXIDES
COMPOSITE MATERIALS
PIGMENTS
SCANNING ELECTRON MICROSCOPY
CHALCOGENIDES
ELECTRON MICROSCOPY
IMPEDANCE
MATERIALS
MICROSCOPY
ORGANIC COMPOUNDS
ORGANIC POLYMERS
OXIDES
OXYGEN COMPOUNDS
POLYMERS
POLYOLEFINS
TRANSITION ELEMENT COMPOUNDS
VANADIUM COMPOUNDS
360606* - Other Materials- Physical Properties- (1992-)