Cover of Electrets, 3rd edition, vol. 1

Electrets, 3rd edition, vol. 1

G. Sessler, ed.

(1998) xv + 472 pages

Vol. I. Electrets have emerged as invaluable components in an ever increasing number of applications ranging from air filters to microphones. This volume presents the fundamental aspects of electret behavior as well as a detailed review of recent work in this area. The broad scope extends from physical principles to experimental work. Thorough coverage of the commercially important polymer electrets. Extensive references for each chapter. Over 100 figures. Reprint of the 2nd edition with updates.



History of electret research; survey of physical properties

Physical principles of electrets

Electric fields, forces, and currents; charging and polarizing methods (forming methods); triboelectricity, contact electrification; methods for measuring charge density; methods for measuring charge distributions; methods for discriminating between polarization and real charges; permanent dipole polarization and real-charge storage

Thermally stimulated discharge of electrets

Mechanisms responsible for TSD; experimental techniques; methods for unraveling the discharge processes; applications of TSD; theory of current TSD by dipole disorientation; theory of current TSD by the self-motion of charges; evaluation of TSD current data; current TSD and dielectric measurements; current TSD arising from the detrapping of charges; some illustrative results of current TSD of heterocharged; electrets; current TSD of heterogeneous systems; disorientation; theory and practice of charge TSD; TSD of thin films and semiconductor devices; analysis of charge detrapping by other techniques; review of information obtainable from TSD; conclusions and prospects

Radiation-induced charge storage and polarization effects

Radiation-induced conductivity; general features of excess-charge transport; electron beam charging; charge diagnostics by transient analysis; gamma-beam charging; dosimetry

Piezo- and pyroelectric properties

Thermodynamic definitions; physical description of an electret; symmetry and tensor components; structure; properties of semicrystalline polymers; measurements and data; dipole model applied to semicrystalline polymers


Electrets in biomaterials and biopolymers; General concepts in electret research; other dielectric techniques complementary to TSD; proteins; bound water (structured water or biowater); polysaccharides and polynucleotides; enzymes; thermally stimulated pressure and bound water; bone; artificial biomaterials; biomedical applications; natural electrets


Electret transducers; electrophotography; electrostatic recording; electret air filters; electret motors and generators; electret dosimeters; piezoelectric polymer transducers; pyroelectric polymer devices

Recent progress in electret research

Physical principles; thermally stimulated discharge of electrets; radiation effects; piezo-, pyro-, and ferroelectric properties; polymer electrets; bioelectrets; applications