Preparation of Spherical MgCl_2/SiO_2/THF-Supported Late-Transition Metal Catalysts for Ethylene Pol

来源 :China Petroleum Processing & Petrochemical Technology | 被引量 : 0次 | 上传用户:hq260
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A facile and user friendly technique to immobilize the late-transition metal complexes on spherical MgCl2/SiO2/THF support has been developed. The spherical MgCl2/SiO2/THF-supported late-transition metal catalysts 2,6-bis-[1-(2,6-dimethylphenylimino)ethyl]pyridine iron(II) dichloride(SC-A) and 1,4-bis(2,6-dimethylphenyl)- acenaphthene diimine nickel(II) dibromide(SC-B) for ethylene polymerization has been prepared by spray-drying technique using tetrahydrofuran suspension containing MgCl2, SiO2 and late-transition metal complexes. The catalysts were characterized by BET, XRD, SEM and the polymers were analyzed using GPC, DSC and 13C-NMR. The test results show that spray-drying is a very effective method for immobilizing late-transition metal catalysts for ethylene polymerization. Among six kinds of cocatalysts for olefin polymerization, TMA and TEA were confirmed to be more effective than other compounds for the ethylene polymerization system using the catalyst SC-A. For the case of the catalyst SC-B, DEAC showed the best performance as cocatalysts in ethylene polymerization. The replication of the catalyst morphology was found in the resultant polyethylene. A facile and user friendly technique to immobilize the late-transition metal complexes on spherical MgCl2 / SiO2 / THF support. The spherical MgCl2 / SiO2 / THF- supported late- transition metal catalysts 2,6- bis- [1- 2,6-dimethylphenylimino) ethyl] pyridine iron (II) dichloride (SC-A) and 1,4-bis prepared by spray-drying technique using tetrahydrofuran suspension containing MgCl2, SiO2 and late-transition metal complexes. The results were showed by that BETA, XRD, SEM and the polymers were analyzed using GPC, DSC and 13C-NMR -drying is a very effective method for immobilizing late-transition metal catalysts for ethylene polymerization. Among six kinds of cocatalysts for olefin polymerization, TMA and TEA were confirmed to be more effective than other compounds for the ethylene polymerization system using the catalyst SC-A For the case of th e catalyst SC-B, DEAC showed the best performance as cocatalysts in ethylene polymerization. The replication of the catalyst morphology was found in the resultant polyethylene.
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