High-field electrical properties of LDPE films prepared using new catalyst

New Low Density Polyethylene (m-LDPE) prepared using metallocene catalyst has a narrower composition distribution and a molecular weight distribution than Linear-Low Density Polyethylene (LLDPE) using Ziegler catalyst. We compared the electrical insulating properties of m-LDPE films and conventional LLDPE films. The high-field current of m-LDPE was found to be lower than that of LLDPE. The difference in current increased with the decrease of temperature. The high-field current was much suppressed in m-LDPE with a low melting point. The impulse breakdown strength of m-LDPE increased with the decrease of temperature. The insulating properties of m-LDPE with a low melting point were improved at 30/spl deg/C. These results were explained by a fact that m-LDPE with a low melting point includes more low-molecular-weight components.