Polymerization of styrene with tetradentate chelated α-diimine nickel(II) complexes/MAO catalyst systems: Catalytic behavior and microstructure of polystyrene

► Tetrachelated α-diimine nickel complexes are active in the styrene polymerization. ► High catalytic activities are obtained when methylaluminoxane is used as cocatalyst. ► The catalyst produces isotactic-enriched polystyrenes (isotactic contents: 73-75.5%). ► The polystyrenes obtained have molecular weights in the range 7-18 × 103 g/mol. ► The polystyrenes synthesised are originated by a coordination addition mechanism.