Porphyrin metal complex covered with polystyrene (PS) arm chains was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization of styrene from the porphyrin metal (Cu) complex with chain transfer agents (CTA) in the presence of AIBN at 80 degrees C (PDI < 1.2). Obtained PS covered porphyrin metal complex was then mixed with different molar ratio of styrene-(ethylene-co-butylene)-styrene (SEBS) triblock copolymer to give well-defined morphologies such as cylinder and lamella structures, where the porphyrin metal complex was selectively dispersed into the PS domain of the SEBS triblock copolymer. These materials could be expected to show interesting electroactive properties, because of high dielectric constant (k) and elastomeric property from the porphyrin metal complex and the SEBS triblock copolymer elastomer, respectively.