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Synthesis and Characterization of Novel Chromium Catalyst and Polyethylene with High Molecular Weigh Synthesis and Characterization of Novel Chromium Catalyst and Polyethylene with High Molecular Weigh

Synthesis and Characterization of Novel Chromium Catalyst and Polyethylene with High Molecular Weigh

  • 期刊名字:武漢理工大學學報(材料科學版)英
  • 文件大?。?/li>
  • 論文作者:CHENG Zhengzai,SUN Junquan,LI
  • 作者單位:College of Material and Chemical Engineering,Institute of Chemical & Environment Engineering,State Key Laboratory of Ele
  • 更新時間:2022-12-12
  • 下載次數(shù):
論文簡介

Mononuclear carbon bridged cyclopentadienyl chromium complexes of the type [(C5H4)C(C5H10)CH2(C5H4N)]CrCl2 (1), [(C5H4)C(CH3)2CH2(C5H4N)]CrCl2 (2) and homodinuclear chromium complex of the type (CH3)2C{[(C5H3)C(CH3)2CH2(C5H4N)]CrCl2}2 (3) were prepared by treatment of the lithium salts of cyclopentadiene ligands with pyridyl group with CrCl3(THF)3 in THF solution. All complexes were structurally characterized by mass spectra and elemental analysis. The structure of complex 1 was determined by X-ray diffraction analysis. Activated by MAO, complexes 1 and 2 are efficient catalysts in the polymerization of ethylene yielding polyethylene (PE) with a high molecular weight (MV ranging from 225800 to 637800 g·mol-1, 30 ≤Tp≤70℃ under 0.9 MPa monomer pressure ). High activities of polymerization are related to the unique electronic and steric structure of complexes 1 and 2 .The melting points of the polymers determined by DSC and characterization data of 13C NMR all show the synthesis of linear polyethylene (LPE) with a low branching extent.

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