Aluminoxane

Aluminoxanes refer to compounds that are obtained by the partial hydrolysis of trialkylaluminium compounds. Aluminoxanes serve as activators for catalytic olefin polymerisation, such as the Ziegler-Natta catalyst. They also serve a function as scavenger for impurities (e.g. water) in reactions that are sensitive to these impurities.

Examples of aluminoxanes include:

The hydrolysis of trialkylaluminium compounds is a highly exothermic process, and the starting trialkylaluminium compounds are often pyrophoric (i.e. burns on contact with air).

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