Electric-field-induced formation of a conducting channel in a dielectric polymer film

Bipolar model for electrical breakdown in polyethylene materials under dc high electrical fields

“…The obtained values of E B in all Fig. 4(aed) are in the same range of the electrical breakdown field reported in literature [14,16,26,27]. For example in Ref.…”

Ageing and breakdown of thin insulating polymer films

“…13,15,16 According to estimates, the current density in the breakdown channel can be higher than 10 5 A/cm 2 . 9,13,14 The fast abrupt current growth is one of key problems in the physics of breakdown of insulators. To explain it, the concept of electron avalanches resulting from impact ionization of polymer macromolecules is often used.…”

“…1,5,11 The breakdown channel diameter in thin polymer films is typically several microns in size, irrespective of the electrode area. [12][13][14] Therefore, the electrical breakdown has a local nature. The polymer breakdown current is characterized by a fast abrupt increase (by several orders of magnitude during 10 À8 -10 À7 s).…”

Hyperbranched electroactive azo polyamide based on oligoaniline: Synthesis, characterization, and dielectric properties

“…Hence they were incapable of providing enough space charge accumulated at the interface of the polymer, which account for the observation that pristine electroactive polymer possessed dielectric constant corresponding to that of traditional polymers. 34 It was noted that the dielectric constant showed a frequency dependence and the dielectric constant decreased signicantly with the increase of frequency, resulting from the AC-conductivity increasing with the frequency at a higher frequency 35,36 and the dipoles and charge carriers within the polymer failing to keep up with increasing AC frequency. 37 Furthermore, the hyperbranched polymer pre- sented higher dielectric constants compared with the similar linear polymer reported before, 18 probobaly because of the highly branched three-dimensional molecular architecture and the high content of the oligoaniline segments.…”