Tert-Butyl Alumoxanes: Synthetic Analogs for Methyl Alumoxane (MAO) and NewCatalytic Routes to Polyolefins and Polyketones

摘要

Alumoxanes are the products from the partial hydrolysis of aluminum compounds.While they have been known for over 30 years, and as a class of chemical are highly important industrially, there has been almost no basic understanding of their structure, reactivity, or potential as new inorganic polymers. The aim of this research was to gain a fundamental understanding of alumoxanes and to enable multiple practical applications to be generated from such understanding. Three areas were originally targeted: (1) alumoxanes as ceramic precursors, (2) alkylalumoxanes as polymerization catalysts, and (3) alumoxanes as materials in their own right. Significant advances have been made in the first two areas. We demonstrated that alumoxanes formed from the hydrolysis of aluminum compounds during ceramic synthesis are not linear polymers as previously depicted, but nano-sized molecules consisting of a boehmite-like core and an organic periphery. This allowed for the rational synthesis of alumoxanes from a commercially viable starting material, boehmite (Al(O)(OH)). We have previously crystallographically characterized alkylalumoxanes and shown that the active catalysts are cages whose activity is dependent on their 'latent Lewis acidity'. Future research is primarily directed towards the application of alumoxanes as materials for new Li(+) and H(+) electrolytes for battery and fuel cell applications, photochromic materials, polymer lasers, and NLO materials.