Titanium Indenoindolyl Catalyst for High-Temperature Olefin Polymerization

The patent modifies the catalyst system by changing the ligand parameters on the metal center (specifically using cyclopentadienyl ligands with specific substituents) and adjusting the activation strategy to achieve high activity at elevated temperatures. The catalyst system includes a metal center with specific ligand configurations that enable efficient polymerization at high temperatures while maintaining high catalyst activity.

The patent employs a composite catalyst system comprising multiple components: a pre-polymerization catalyst with specific ligand structures, a boron-based catalyst activator, an alkylaluminoxane co-catalyst, and a hindered phenol compound. This composite approach combines the advantages of each component to achieve both high temperature operation and high catalyst activity simultaneously.

The patent applies local quality by introducing specific ligand structures with particular substituents at specific positions on the metal center. The cyclopentadienyl ligands have specific substituents (R1-R12 groups) that are strategically positioned to control the polymerization mechanism, resulting in precise control over molecular weight and short chain branching characteristics.

The patent employs preliminary action through the use of a pre-polymerization catalyst that is activated in advance by a boron-based catalyst activator before the actual polymerization occurs. This pre-activation step prepares the catalyst system in an optimal state to produce copolymers with desired molecular weight and branching characteristics, while the hindered phenol compound further modifies the active sites to achieve the target polymer properties.