ELECTRICAL CHARACTERISTICS OF THE BLENDS OF SILICON AND EPDM OUTDOOR INSULATORS

Polymeric insulators are widely used as outd oor H.V insulators due to their superior service properties in the presence of heavy polluted and wet condition, resistance to vandalism and high dielectric strength voltage. Polymer insulators particularly those made of ethylene propylene diene monomer an d silicone rubber are increasingly being used today and blending of two polymers is an attractive way to develop a new material combines the best properties of these two materials. In 1986 the first alloy of SiR/EPDM was prepared. Today the most widely use d insulator weather shed materials are SiR/EPDM blends. This paper aims to improve SiR/EPDM blends electrical properties (dielectric strength) for high voltage insulators. Blends of SiR with EPDM were prepared with 0%, 25%, 50%, 75% and 100% by weight per centages concentration. The dielectric strength of the blends was tested in several conditions such as (dry, wet, low and high salinity of water and ultra violet). Also dielectric strength of blends was tested after being exposed to thermal aging for 24 hours(hrs) in high temperatures (60, 100 and 130 o C).