Copolymerizations of ethylene with 1-decene over various ANSA-metallocene complexes combined with Al(i-Bu)3/[CPh3][B(C6F5)4] cocatalyst

Copolymerizations of ethylene with 1-decene were carried out with a series of stereospecific metallocene compounds, C₂H₄[Ind]₂Zr(NMe₂)₂ (1), C₂H₄[Ind]₂Hf(NMe₂)₂ (2), (CH₃)₂Si(1-C₅H₂-2-CH₃-4-^tC₄H₉)₂Zr(NMe₂)₂ (3), C₂H₄(Fluo)(Cp)Zr(NMe₂)₂ (4), (CH₃)₂C(Fluo)(Cp)Zr(NMe₂)₂ (5) (Cp = η⁵-cyclopen-tadienyl, Ind = η⁵-indenyl Fluo = η⁵-fluorenyl), combined with Al(i-Bu)₃/[CPh₃][B(C₆F₅)₄] cocatalyst. The copolymerization rate decreased in the order of 3 > 1 > 2 ∼ 4 > 5 and the 1-decene reactivity decreased in the order of 2 > 5 > 1 ∼ 4 > 3. The reactivity product of ethylene and 1-decene (r_E × r_D) was below 1 except 3 catalyst, corresponding to random copolymer structures with an alternating character. The melting point, crystallinity, intrinsic viscosity and density of the 1-decene/ethylene copolymers decreased markedly with an increase in the 1-decene content, regardless of the type of catalytic system.