Novel dinuclear half-titanocene-producing styrene/ethylene copolymers containing syndiotactic styrene/styrene sequences

The synthesis and characterization of a novel titanium complex, {[C ₅(CH₃)₅]ClTi}₂O₂C ₂(CH₃)₄(μ-O) (2), which has two titanium metal centers linked by heteroleptic bridges, oxo and pinacolato, is described. The compound shows good stability under air. The 2/modified methylalumoxane (MMAO) catalytic system produces ethylene/styrene interpolymers (ESIs) containing syndiotactic styrene/styrene sequences (syndiotactic polystyrene blocks) with a high styrene content. To the best of our knowledge, this is the first example of a group-4-based catalytic system producing an ESI with syndiotactic polystyrene blocks. A dinuclear half-titanocene complex containing oxo and pinacolato heteroleptic bridges producing ethylene/styrene interpolymers containing syndiotactic styrene/styrene sequences is described. A catalytic system using this complex produces an ethylene/styrene interpolymer containing sPS blocks with a high styrene content. To the best of the authors' knowledge, this is the first group 4-based catalytic system producing ESIs containing sPS blocks.