Tuning the ligand structure in metallocene polymerization catalysts

Meso-[Me₂Si(2-Me-4,6-ⁱPr₂Ind)₂ZrCl₂ was synthesized in a pure form and used as catalyst for the copolymerization of ethene and α-olefins. The results are compared with polymers obtained by C₁-symmetric metallocenes and constrained geometry catalysts. The activity of the meso form is remarkable high and reaches more than 100000 kg polymer/mol Zr · h. The ligand structure has large influence on the incorporation of 1-octene forming thermoplastics (LLDPE) and thermoplastic elastomers (POE).