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The pyroelectric response Uπ of triglycine sulphate/polyethylene oxide composites is investigated by the photothermomodulation method in the course of polarization reversal under the action of an external voltage V. The thermowave profiles derived from the dependence of Uπ on the IR-flux modulation frequency indicate changes of the distribution of pyroelectric parameters over the thickness at different polarization reversal stages. The study of Uπ (V)-loops shows a large start-finish voltage interval of the polarization reversal. Two phases in the polarization reversal that are distinguished by a difference in time scales in the polarization switching process are revealed. The thermowave probing proved to be an efficient tool for studying the polarization reversal in ferroelectric particles in multiphase matrices. [ABSTRACT FROM AUTHOR]

Preliminary results of polymer poly(ethylene oxide) (PEO) with β-LiNH4SO4 (LAS) or Li(N2H5)SO4 (LHS) composites are presented. It was shown that Raman spectra did not reveal the existence of any complexes in the composites under studies. Electrical conductivity of the composites with LAS is about one order of magnitude higher than that for PEO and two orders higher than for LAS at room temperature, whereas for composites with LHS conductivity is lower than for LHS crystals. [ABSTRACT FROM AUTHOR]

Dielectric response (100 Hz-1 MHz) and pyroelectric response (light modulation frequency range 10 Hz-1 kHz) of ferroelectric P(VDF/TrFE)(50/50) copolymer loaded with relaxor PLZT 9.5/65/35 ceramic powder of 10 nm crystallite size and ∼700 nm aggregates was studied. Though the dielectric permittivity of the composites increases due to high permittivity of the ceramic, their dielectric response is determined by dielectric relaxation processes of the polymer matrix. The dispersive dielectric anomalies of PLZT-0.9/65/35 relaxor ceramic affect mainly the dielectric absorption of the composites in the range of dipolar relaxation in the crystallite phase of the copolymer. The composites exhibit pyroelectric activity proper for application in operation frequency up to 1 kHz and temperature range 290-310 K. [ABSTRACT FROM AUTHOR]