Results 211 to 220 of about 19,417 (263)

SPICE model for lossy piezoelectric polymers

IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2009
This work presents the transmission line equivalent model for lossy piezoelectric polymers and its SPICE implementation. The model includes the mechanical/viscoelastic, dielectric/electrical, and piezoelectric/electromechanical losses in a novel way by using complex elastic, dielectric, and piezoelectric constants obtained from the measured impedances ...
DAHIYA R, VALLE, MAURIZIO, LORENZELLI L.
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Piezoelectricity of polymer films

The Journal of the Acoustical Society of America, 1978
Origins of piezoelectricity of polymer films are classified into three: (a) internal strain, (b) strain dependence of spontaneous polarization, and (c) embedded charges coupled with mechanical and/or dielectric heterogeneity. Recent work on piezoelectricity of the polyvinylidene fluoride electret, which arises from mechanism (b) and/or (c), is briefly ...
Y. Wada, R. Hayakawa, K. Namiki
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Synthetic Piezoelectric Polymers

Piezoelectric polymers combine the electro-mechanical and mechano-electrical functional response of piezoelectric materials and the mechanical flexibility and simple processability of polymers. This combination opens the way for a wide variety of applications in areas including biomedicine, aerospace and automotive, among others.
Fernandes, L., Costa, Carlos Miguel Silva, Lanceros-Mendez, S.   +2 more
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Piezoelectricity and Pyroelectricity of Polymers

Japanese Journal of Applied Physics, 1976
This article surveys theoretical and experimental work on piezo- and pyroelectricity of polymers in the 1970's with special emphasis on the origins of these properties. The origins are classified into three types: (A) internal strain (§2), (B) strain- and temperature-dependences of spontaneous polarization (§3), and (C) elastic and/or dielectric ...
Yasaku Wada, Reinosuke Hayakawa
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Piezoelectric polymer electrets

IEEE Transactions on Dielectrics and Electrical Insulation, 1996
In this review the physical properties, mechanisms and models are reviewed which explain the high piezoelectricity of the ferroelectric polymers of the polyvinylidene fluoride (PVDF) family, the odd nylons, the vinylidene cyanide (VDCN) copolymers and polyurea.
G. Eberle, H. Schmidt, W. Eisenmenger
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Piezoelectric properties of biological polymers

Quarterly Reviews of Biophysics, 1983
Piezoelectricity and pyroelectricity in wool and hair were observed by Martin early in 1941. The piezoelectric effect in wood was investigated in detail by Bazhenov (1961). Both converse and direct effect of shear piezoelectricity in wood was demonstrated by Fukada (1955). Bending piezoelectricity in bone was first discovered by Yasuda (1953).
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Piezoelectricity in polymers and biological materials

Ultrasonics, 1968
Abstract The piezoelectric effect in polymers is usually explained in terms of the uniaxial orientation of the polymer crystallites and the classical piezoelectric property of these crystallites. Polarization caused by stress gradient seems to be necessary to the understanding of the geometrical relationship between stress and polarization.
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Piezoelectric polymer hydrophone

The Journal of the Acoustical Society of America, 1983
A piezoelectric polymer hydrophone including a single flexible sheet of a ezoelectric polymer having a plurality of electrode strips on the top and bottom of the sheet. The electrode strips at the top are staggered by one half the width of a strip relative to the corresponding strips at the bottom of the sheet.
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The piezoelectric effect in polymers

Polymer Mechanics, 1972
A series of polymers with varying polarity and chain rigidity has been investigated. On the basis of the results obtained it is concluded that piezoelectric properties are to be found in polarized polymers with small dipole groups and a rigid chain due to their polarity.
N. M. Kocharyan, Kh. B. Pachadzhyan
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Piezoelectricity in polymer electrets

Journal of Applied Physics, 1982
The model of Mopsik and Broadhurst for piezoelectricity in polymer electrets is reconsidered and further developed. The main features of the model are reviewed with particular attention directed to tensorial aspects of the piezoelectric effect. A characteristic difference is pointed out in the patterns of piezoelectric response attributed to two ...
J. Strathdee, W. H. Robinson
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