High‐field conduction and carrier traps in polyethylene copolymerized with various monomers

Abstract

The electrical breakdown and electrical conduction of ethylene copolymers have been studied. The electric strength of ethylene copolymers containing an optimum content of halogen moieties such as bromophenyl and fluoroethylene groups was found to be higher than that of LDPE over the wide temperature range from −196°C to 90°C. Also, conduction currents in the copolymers were suppressed at high electric fields. X‐ray‐induced thermally stimulated currents (TSC) revealed that halogen comonomers act as carrier traps with a depth of about 0.4 eV. Consequently, the introduction of comonomer‐containing halogen groups into polyethylene suppresses electron acceleration as a result of an increase in trapping and scattering of conduction electrons. This leads to an increase in electric strength which is determined by the electron avalanche breakdown.

Aromatic Polythiourea Dielectrics with Ultrahigh Breakdown Field Strength, Low Dielectric Loss, and High Electric Energy Density

“…This apparent mobility can be many orders of magnitude lower than the intrinsic carrier mobility, which explains the strong suppression of the conduction current 17. This mechanism is also supported by experimental observations by Ishino et al, which show that polyethylene copolymers with highly polar groups exhibited higher breakdown strength and lower high‐field conduction loss than pure polyethylene 21. Finally, having a uniform film is also very important to the electric characteristics of the materials, and atomic force microscopy (AFM) images of the ArPTU films reveal a very smooth film surface.…”

Click-In Ferroelectric Nanoparticles for Dielectric Energy Storage

“…The energy density of dielectric capacitors is approximately 3 orders of magnitude less than that of Li-ion technologies. Improving the energy density of dielectric capacitors has been of particular interest over the past 10 years focusing on high dielectric constant ceramics, [26][27][28][29][30][31][32][33][34][35][36][37][38][39] high breakdown polymers, [40][41][42][43][44][45][46][47][48][49][50][51] and composites of these materials. 24,32,[52][53][54][55][56][57][58][59][60][61] Research on dielectric capacitors aims to improve the two material properties that dictate the energy density of a device (i.e.…”

“…The energy density of dielectric capacitors is approximately 3 orders of magnitude less than that of Li-ion technologies. Improving the energy density of dielectric capacitors has been of particular interest over the past 10 years focusing on high dielectric constant ceramics, − high breakdown polymers, − and composites of these materials. ,,− Research on dielectric capacitors aims to improve the two material properties that dictate the energy density of a device (i.e., dielectric constant and breakdown field). From the volumetric energy eq , it is clear that the most significant contribution is from the breakdown field, E b , which increases the energy density by its square.…”

Photonic curing of aromatic thiol–ene click dielectric capacitors via inkjet printing

“…The current drawback of a dielectric capacitor is that the total gravimetric capacity is being dwarfed by Li-ion batteries by 3 orders of magnitude, requiring signicantly greater amounts of material to be used, increasing the cost and weight of any design. Recently, there has been increased attention on the production of high energy density capacitors through the use of high dielectric ceramics, [7][8][9][10][11][12][13][14][15][16][17][18] high breakdown polymers, [19][20][21][22][23][24][25][26][27][28][29][30] and composites of those materials. 5,13,[31][32][33][34][35][36][37][38] There have been signicant improvements in the development of materials, however, the necessity of large scale manufacturing processes have been overlooked in the pursuit of the largest possible dielectric constants and breakdown elds.…”