双(咪唑啉-2-亚胺)吡啶铁、镍配合物引发的烯烃聚合行为

Olefin polymerization behavior of Fe,Ni complexes bearing bis(imidazolin-2-imino) pyridine ligand

研究了含双(咪唑啉-2-亚胺)吡啶配体的铁、镍配合物在不同温度、不同助催化剂下对烯烃聚合行为的研究。铁配合物经改性甲基铝氧烷(MMAO)的活化对乙烯聚合具有良好的活性,并于60℃达到最高活性为1.68×10~6g PE/mol/h,且在较高的温度下活性并未衰减,所得聚乙烯的数均分子量可高达22万。镍配合物分别在助催化剂MMAO和甲基铝氧烷(MAO)的作用下对降冰片烯均表现出很高的活性,MAO体系的活性最高达7.65×10~7g/mol/h,产物的数均分子量达到50万;MMAO体系的活性虽然比MAO体系低(1.464×10~7g/mol/h),但产物的数均分子量最高可达150万。

Olefin polymerization behavior of Fe,Ni complexes bearing bis（imidazolin-2-imino） pyridine ligandin combination with different cocatalyst was studied by changingpolymerization temperature.Fe complex activated by modified methyaluminoxane（MMAO） showed excellent activity for ethylenepolymerization with highest activity of up to 1.68 × 10^6 g PE/mol/h at 60 ℃ and didnot decreased significantly at higher temperature.Molecular weight of polyethylene decreased by increasing the polymerization temperature and with a highest value of 220 000.Nickel complex activated by MMAO and methyaluminoxane（MAO）,respectively,showed good activity for norbornene polymerization under different polymerization temperature.The MAO system showed high polymerization activity value of 7.65 × 10^7g/mol/h toproduce high molecular weight polynorbornene（Mn = 500 000）,while the MMAO system showed a lower polymerization activity value（1.464 × 10^7g/mol/h）,butultrahigh molecular weight polynorbornene（Mn = 1 500 000） was obtained.