Space charge in polymers, particularly polyethylene

Space Charge Behavior in Low-Density Polyethylene

The space charge distribution in low-density polyethylene (LDPE) was measured with the pulsed electroacoustic (PEA) method. We used three types of LDPE: LDPE-L and LDPE-H were prepared by the high pressure process, and m-LDPE was polymerized with a metallocene catalyst. Space charge in LDPE strongly depended upon the electrode material. Semiconductive electrodes enhanced carrier injection into ...

Space-charge dynamics in photorefractive polymers

The model of space-charge formation in photorefractive polymers due to Schildkraut and Buettner has been modified to include thermally accessible deep traps as well as shallow traps. The dynamic equations have been solved semiempirically using independent measurements of photoconductive properties to predict photorefractive dynamics. Dependencies of the dynamics on charge generation, mobility, ...

Space-charge dynamic in polyethylene: from dc to ac stress

Time-resolved space charge profiles obtained in low density polyethylene under sinusoidal or square AC stress for frequencies going from DC to 10 Hz, temperature from 25 to 50°C and fields of 30 or 40 kV/mm are presented. It is shown that most of the features observed under DC stress (generation of carriers of the two polarities with non-symmetrical amount and velocity) are still active under A...

Options for Pre-charge Detention in Particularly Complex Terrorist Cases

The influence of oxidation on space charge formation in gamma-irradiated low-density polyethylene

The research presented in this paper investigates the role of oxidation in the formation of space charge in gammairradiated low-density polyethylene after being electrically stressed under dc voltage. Polyethylene plaques both with and without antioxidant were irradiated up to 500 kGy using a Co gamma source and space charge distributions were measured using the piezoelectric induced pressure w...