Effect of additive and polarization temperature on space charge formation in polyethylene

A thermal step method was used to investigate space charge formation in low-density polyethylene (LDPE) and LDPE doped with an inorganic additive. Space charge was formed at a field of about 3.3 × 10⁵ Vcm^-1 and at two different temperatures, 40°C and 70°C. Results indicate that the addition of such an additive considerably reduced the density of the remnant space charge in the doped material and appreciably changed its distribution pattern. It is also shown that the remnant space charge in the doped material is sensitive to the forming temperature, while in the plain material the space charge appears to be insensitive to the change of temperature within the temperature range used