Dielectric behavior of O3-type piezoelectric composites

Dielectric properties of ferroelectric ceramic loaded P(VDF/TFE) polymer were studied in the frequency range 20 Hz to 1 GHz and at temperatures from 110 to 420 K. A simple relaxation with activation energy of 1.8 eV, observed at temperatures from 225 to 275 K and frequencies from 20 Hz to approximately 5 kHz, is related to the dielectric absorption in the amorphous phase of the polymer. At higher frequencies and temperatures complex and non-Arrhenius behavior of the main absorption of the O3-type composite is observed. Moreover, in the frequency range <5 kHz a small dielectric absorption is found at 300 K and ascribed to the relaxation of polar defects. At higher temperatures (350 to 400 K) dielectric absorption related to the alpha /sub c/ relaxation of the polymer was measured for the composites.<
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