Dielectric design of LDPE properties: With the help of double-core Si/SiO2 and Carbon Black

Low-density Polyethylene (LDPE) was modified by using simultaneously 2 additives. Each additive had a specific attribute. Silicon was used. Using TEM with EELS, it was proved first that the passivated version constituted a double core consisting of Si surrounded by a nanometric layer of amorphous Silica (SiO
₂
). Thus Si brought the possibility of an enlarged dielectric storage capacity with a barrier controlling the electrical charge movement (via SiO
₂
). Silicon was used in conjunction with Carbon Black (CB) and produced, upon some conditions, enlarged dielectric storage yet with intempestive conversion to a conducting state. At low voltage, LDPE containing 5 wt% CB and 3% or 0.25% Si remained insulating materials. During breakdown conditions with a 2 kV/s rise, only the composite containing 0.25 wt% CB and 3 wt% Si exhibited insulating conditions. These results draw attention to the importance of performing material system evaluation under dynamical conditions.