Role of trimethylaluminum on the zirconocene-methylaluminoxane-catalyzed polymerization of ethylene

Reactivity of Metallocene Catalysts for Olefin Polymerization: Influence of Activator Nature and Structure

“…An increase in the catalytic activity, along with a change in the kinetic profile from decay-type to steady-type was observed when TMA is added to MAO. [95] Similarly, MAO can be partially replaced by TMA without a loss of activity. [96] It has been proposed that TMA stabilizes the active centers formed from Cp 2 ZrCl 2 and extends the catalyst lifetime.…”

A DFT quantum-chemical study on the structures and active sites of polymethylaluminoxane

“…Several authors note that the presence of TMA in MAO is essential for the high activity of metallocene catalysts [13][14][15] . With regard to this, we carried out the quantum-chemical calculations of reaction between dimeric TMA and MAO with cage structure (n = 4, 8, 12).…”

Novel stabilization system for polypropylene via the Ziegler–Natta catalyzed polymerization in the presence of aluminum aryloxide

“…Phenolic OH was confirmed to be regenerated during hydrolysis of aluminum aryloxide, but the other part of phenolic antioxidants were decomposed. 19 In this study, the propylene polymerization was conducted by using supported type Ziegler-Natta catalysts in combination with hindered phenols having no decomposable functional groups as phenolic antioxidants and/or their aluminum aryloxides derived from the reaction of antioxidants with aluminum alkyls. The influence of the aluminum aryloxides on catalyst performance, polymerization behavior, polymer characteristics, and the stabilization level of resulted polypropylene powders were evaluated from the standpoint of applicability of postpelletizing method.…”