| Abstract
| - A new effective constrained geometry catalyst precursor for the ethylene/1-octene copolymerization, namely 2-methylbenz[e]indenylamido complex [η5:η-(2-MeBenzInd)SiMe2NtBu]TiCl2 (4),was synthesized. Activated with methylaluminoxane (MAO), the complex 4 showed (a) an improvedcopolymerization activity and stability, (b) an enhanced comonomer incorporation in the copolymer, and(c) most importantly, an increased copolymer molecular weight, when compared with the previouslyemployed catalysts. The polymerization conditions were found to have a significant effect on the catalystactivity, 1-octene incorporation, molecular weight, and even copolymer microstructure. For the copolymerization parameters, the values rE ≈ 2.20 for ethylene and rO ≈ 0.55 for 1-octene with rE·rO ≈ 1.21were obtained, reflecting a pronounced tendency for the random distribution of the comonomers in thecopolymer chain. The 13C NMR analysis revealed that the E−O copolymer generated by the MAO-activated complex 4 has a regioirregular arrangement of the 1-octene repeat units as a result of sometail-to-tail incorporation of the 1-octene comonomer.
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