A series of alkylaluminoxanes(TEAO, BTEAO, TAAO and BEBAO) were synthesized by hydrolysis of aluminium alkyls and modified with para-fluorophenylboric acid. Their cocatalytic performances, especially their effects on molecular weight and molecular weight distribution of polyethylene catalyzed by{ 2C 5H 3N}FeCl 2(Ar=2,6-diisopropylphenyl) (1) were studied. Under the action of iron-based catalyst together with all of the four alkylaluminoxanes linear high-density polyethylene with broad or bimodal molecular weight distribution was formed, and the molecular weight and molecular weight distribution of polyethylene could be adjusted to some extent by changing n(Al)/n(Fe) ratios and architecture of aluminoxanes.
