Space charge dynamics in low density polyethylene under DC electric fields

In this paper space charge dynamics in low-density polyethylene (LDPE) under different dc electric fields, ranging from 25 κV/mm to 125 κV/mm, have been investigated using the pulsed electroacoustic (PEA) technique. Bipolar space charges have been found to present in the sample and the amount of charge increases with both the applied electric field and the duration of electric field applied. Double injection is believed to be responsible for the charge measured. Negative charge dominates due to electrode configuration used in the research. The formation of charge leads to an increase in the maximum electric field. Results show that the maximum electric field depends on both the magnitude and the duration of the applied field. The charge decay after the removal of the applied field shows a fast decaying rate for the charge formed at high applied electric field.