Compatibilizing effect of SEBS for electrical properties of LDPE/PS blends

In the previous study, we observed compatibilizing effects of low density polyethylene (LDPE)/polystyrene (PS) with polystyrene-block-poly(ethylene-co-butylene)-block-polystyrene (SEBS), a triblock copolymer. Blends consisting of 70 wt.-% LDPE and 30 wt.-% PS were prepared with a SEBS concentration of up to 10 wt.-%. This study examined the electrical properties such as the electrical break-down, water tree length, permittivity and tan δ in the blends. The possibility of using these blends as insulating material substitutes for LDPE was investigated. The electrical break-down strength reached a maximum of 66.67 kV/mm, which is superior to 50.27 kV/mm of the LDPE used as electrical insulators for cables. In addition, the water tree length decreased with increasing SEBS concentration. The water tree lengths of the blends containing SEBS were shorter than that of the LDPE. The permittivity of the blends was 2.28-2.48 F/m, and decreased with increasing SEBS concentration with the exception of S-0. Tan δ of the blends increased smoothly with increasing SEBS content.