A review of developments in thermal techniques for charge profile measurements in polymer electrets

• Paper investigates a detailed review of Thermal Pulse Techniques and Thermal Pulse Techniques.
• Methods of data analysis discussed.
• Pitfalls and Improvements in thermal techniques evaluated.
• Recent advances, applications of Thermal techniques discussed.

A number of methods were evolved during last three decades to understand the internal charge profile of polymer electrets. These methods essentially are based on the propagation of heat or pressure waves inside the charged samples. In both cases, electrical signals are generated due to mechanical or dielectric changes caused by heat diffusion or propagation of a pressure discontinuity in the sample. The charge distribution can be obtained from the electrical response. This paper presents detailed information on the thermal techniques to probe the charge distributions in the thickness direction of the polymer electrets as well as a comprehensive review of thermal data analysis.