铁系后过渡金属催化剂/不同铝氧烷体系制备具有双峰分子量分布的聚乙烯

分子量及其分布对聚烯烃的机械性能和流变性能影响显著．高分子量聚烯烃机械性能好，但加工性能差；低分子量聚烯烃则恰恰相反，机械性能较差，但加工性能好．宽峰或双峰分子量分布聚烯烃同时具有高、低分子量聚烯烃的优点，受到人们的普遍重视．目前，制备宽峰及双峰分子量聚烯烃主要采用物理共混、

Synthesis of Polyethylene with Bimodal Molecular Weight Distribution by Iron-based Late Transition Metal Catalyst/Various Aluminoxanes System

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.