Study On The Synthesis And Applications Of Ortho-quinone Diimine Complexes

Polyethylene is the general purpose synthetic resin that has the largest annual productivity. With the development of human society, the requirement for high performance polyethylene materials keeps increasing. The key for the production of high performance polyethylene product is the catalyst with high activity and high performance. Since the discovery of their catalytic activitiy in the polymerization, oligomerization and copolymerization of ethylene, the the complexes made byα-diimine and late transition metal attracted attention from both academy and industry. It was found that such complexes with certain structures can lead to the formation of highly branched polyethylene with higher molecular weight in ethylene's polymerization. Some otherα-diimine complexes can catalyze the copolymerization of ethylene with polar monomers. Marcomolecule with polar functional groups was thus obtained, which demonstrate some unique properties. Research on synthesis and applications of novel diimine complexes with special structures became an important research direction in that field.The main purpose of this project is the design and synthesis of ortho-quinone diimine complexes and the exploration of their applications in the polymerization and oligomerization of ethylene. It was found through experimental research that 3,5-di-tert-butyl-ortho-quinone can be obtained by oxidation of the corresponding catechol. Reaction of 3,5-di-tert-butyl-ortho-quinone with anilines can form the mono-imine compound, which can be converted to the target product by reacting with a amine and a iron/nickel salt. The complexes thus obtained were applied in the polymerization of ethylene to explore the suitable reaction conditions. It was found that ethylene oligomerization took place by applying complex 3 as catalyst, methylaluminoxane (MAO) as coatalyst. When the reaction was carried out at 30℃, 0.5Mpa, the activity reached 700g/(mmol·cat).