Study On Synthesis,Characterization And Catalytic Properties Of Single Metallocexne Complexes Containing Neutral Amine Ligand Side Arm

Polyolefin products are rich in raw materials,low in price,mature in processing technology and excellent in performance.They are the main chemical synthetic resins and will gradually replace natural rubber in the future.There are many types of olefin polymerization catalysts with different properties,and they can produce a variety of polyolefin products with specific properties.After decades of development,researchers have continuously synthesized new catalysts and found that metallocene catalysts have their unique advantages in continuous exploration.By optimizing the ligand structure and changing the coordinated metal atoms,the catalyst structure and performance can be changed.Products with various uses,so metallocene catalysts still have broad applications in the field of polyolefin catalysts.As soon as the metallocene catalyst with restricted geometric configuration was reported,it has attracted great attention in the metal organic field due to its excellent catalytic performance,and has attracted a large number of scientific research workers.At present,there are current reports on the restricted geometric configuration of rare earth,cobalt,chromium and other metals.Monocyclopentadiene complexes have been studied,but the fourth subgroup transition metals Ti,Zr,Hf are rarely studied.Therefore,this article refers to the literature to synthesize a class of ligands containing neutral amine ligands on the side arms,and obtain 15 types of metal complexes of the fourth subgroup,of which one has been reported in the literature,but there is no catalyst for olefins.Research on nature.The second chapter of this article mainly describes the drugs needed for the experiment and some test and characterization methods.In Chapter 3,four ligands were synthesized using improved experimental methods,and the metal complexes of Ti???,Ti???,Zr???and Hf???were synthesized by the lithium salt method.The metal complexes of Ti???,Zr???and Hf???were characterized by ¹H NMR and ¹³C NMR,and the Ti???complexes were characterized by elemental analysis.At the same time,in the mixture of benzene/n-hexane The crystal of the complex 2-Me₄CpHNMe₂TiCl₂ was cultivated in the solvent and its structure was proved by X-ray single crystal diffraction:the cyclopentadienyl group in the ligand and the amino group on the side chain form a bond with the central metal,and the complex dimerizes The form of body exists.In Chapter 4,this article studies 15 kinds of complexes under the activation of MAO or AlⁱBu₃/Ph₃CB?C₆F₅?₄ to catalytic ethylene homopolymerization and ethylene/1-hexene copolymerization.The 15 kinds of complexes exhibit moderate to high catalytic activity.Among them,under the same polymerization conditions,the activity of the titanium complex is much higher than the catalytic activity of the corresponding zirconium and hafnium complexes,the resulting polymer has a medium to high molecular weight,and the resulting copolymer has a medium comonomer insertion rate?up to 19.5%?.