Highly Efficient Synthesis Of Ethylene/?-olefin/polar Olefin Multicomponent Copolymers By Novel[N,P] Bidenate Ti-based Non-metallocene Catalysts

Polyolefin products have become important parts of human life,and their huge demand and commercial profits continue to stimulate the development of the polyolefin industry.At present,the domestic industrialization technology for low-end special materials for simple olefin homopolymerization has matured.Therefore,the industrialization of high-end polyolefin materials such as olefin elastomers and polar functional polyolefins will become the future of the domestic polyolefin industry.The development trend,whether this trend can be achieved depends on the development of the catalyst.Based on the catalyst infrastructure innovation,green ecological development,atomic economy and low cost concept,this paper designed and synthesized a novel[N,P]bidentate Ti-based non-metallocene catalyst Cat.A-Ti,and[N,Si,N,P]type Ti non-metallocene catalysts Cat.Ll-Ti,Cat.L2-Ti.The effects of ligand structure,polymerization temperature and Al/Ti ratio on the catalyst homopolymerization of ethylene were investigated.It can be found that Cat.A-Ti has the best catalytic performance when the Al/Ti ratio is 550 and the polymerization temperature is 60?,Cat.Ll-Ti and Cat.L2-Ti have the best catalytic performance when the Al/Ti ratio is 450 and the polymerization temperature is 60?.Compared with the three catalysts,Cat.A-Ti catalyzed the highest ethylene homopolymerization activity.When the ethylene pressure was 0.05 MPa and the polymerization temperature was 60?,the activity was as high as 3.35×105 g Polymer·(mol·Ti·h)-1,the molecular weight of polyethylene exceeds 1.4×106 g/mol.The catalyst has simple synthesis,high yield and low raw material cost.It can effectively catalyze the homopolymerization of ethylene when the polymerization temperature is raised to 95?,and the polymerization activity reaches 6.4×104g Polymer·(mol·Ti·h)-1,the molecular weight of polyethylene can reach 38.7×104 g/mol.At the same time,Cat.A-Ti can efficiently catalyze the binary copolymerization of ethylene with 1-hexene,1-octene or 1-dodecene,and the ternary copolymerization of ethylene/1-octene/9-nonen-1-ol.When the ethylene pressure is 0.05MPa and the polymerization temperature is 60?,the binary copolymerization activity of Cat.A-Ti is higher than 2.5×1 05g Polymer·(mol·Ti·h)-1,and the insertion rate of 1-hexene monomer in the molecular chain of the copolymer can reach 6.5mol%;Cat.A-Ti catalyzed the ternary copolymerization activity up to 1.04×105 g Polymer·(mol·Ti·h)-1,the molecular weight of the copolymer is up to 1.12×106 g/mol.The concentration of each monomer in the copolymerization system are adjusted to obtain functionalized polyolefins having 9-decen-l-alcohol insertion rate of 1.91 mol%and 1-octene insertion ratio of 5.01 mol%,and functionalized polyolefins having 1-octene insertion rate of 7.16 mol%and 9-decen-1-ol insertion rate of 1.34 mol%.Inaddition,the hydrophilic property and damping performance of the ethylene/1-octene/9-decen-1-ol terpolymer are better than that of the ethylene/1-octene copolymer.