Dielectric property high electric field

Typical values of electrical properties of the homopolymer without additives and treatments are in the Table 3.8. The values can be substantially changed by the type of cooling and post-treatments, which determine the morphological state of the polymer. Dielectric constants as high as 17 have been measured on oriented samples that have been subjected to high electrical fields (poled) under various conditions to orient polar crystalline form.74... 

The second group consists of properties that are important at very high electric field strengths, such as electric discharge, dielectric breakdown and arc resistance. They may be regarded as the ultimate electrical properties. Properties of the first group are directly related to the chemical structure of the polymer those of the second are greatly complicated by additional influences in the methods of determination. 

The electrical properties of interest for ceramics include conductivity, resistivity, dielectric breakdown strength, dielectric constant, loss factor, and electromechanical coupling. Most ceramics do not have high electrical conductivity, and thus ceramics have found application as electrical insulators for many years. The electrical insulating capability of some ceramics is also retained under high electric field this is referred to as high dielectric breakdown strength... 

DIELECTRIC PROPERTY OF ER FLUIDS UNDER A HIGH ELECTRIC FIELD... 

Electret Another application for plastics which uses the intrinsic properties is in elec-trets (a dielectric body in which a permanent state of electric polarization has been set up). Some materials such as highly polar plastics can be cooled from the melt under an intense electrical field and develop a permanent electrical field that is constantly on or constantly renewable. 

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