6533b7d3fe1ef96bd1260ae5

RESEARCH PRODUCT

Homopolymerization of styrenic monomers and their copolymerization with ethylene using group 4 non‐metallocene catalysts

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Homopolymerization of styrenic monomers (St, p ‐Me‐St, p ‐t Bu‐St, p ‐t BuO‐St) and their copolymerization with ethylene, with the use of [( t Bu2O2NN′)ZrCl]2(μ‐O) (1 ) and ( t Bu2O2NN′)TiCl2 (2 ), where t Bu2O2NN′ = Me2N(CH2)2N(CH2‐2‐O−‐3,5‐t Bu2‐C6H2)2, is explored in the presence of MMAO and (i Bu)3Al/Ph3CB(C6F5)4. The ethylene/styrenic monomers copolymerization with 1 /MMAO produces exclusively copolymers with high activity and good comonomer incorporation whereas the other catalytic systems yield mixtures of copolymers and homopolymers. The use of p ‐alkyl styrene derivatives instead of styrene raises the catalytic activity, comonomer incorporation and molecular weights of the copolymers. Complex 2 exhibits higher activity in homopolymerization of styrenic monomers than 1 irrespective of the kind of the activator employed. A clear dependence is observed for the molecular weight and catalyst activity against the kind of the styrenic monomer. The obtained polymers were atactic and only the complex 2 , when activated by MMAO, promoted the highly syndiospecific polymerization of p ‐Me‐St and p ‐t Bu‐St. Poly(p ‐t BuO‐St) exhibits fiber‐forming properties.