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RESEARCH PRODUCT
The chloro‐substituent enhances performance of 2,4‐bis (imino)pyridylchromium catalysts yielding highly linear polyethylene
Wen-hua SunBadral GansukhQiuyue ZhangYanping MaZygmunt FlisakZygmunt FlisakTongling Liangsubject
ChemistrySubstituentGeneral Chemistryethylene polymerizationCatalysisinfluence of chloro‐substituentInorganic ChemistryLinear low-density polyethyleneBis (imino)pyridinechemistry.chemical_compoundEthylene polymerizationPolymer chemistrychromium precatalysthighly linear polyethylenedescription
The five unsymmetrical 2‐[1‐(2,4‐dibenzhydryl‐6‐chlorophenylimino)ethyl]‐6‐[1‐(arylimino)ethyl]pyridine compounds (aryl: 2,6‐Me2Ph L1 , 2,6‐Et2Ph L2 , 2,6‐i Pr2Ph L3 , 2,4,6‐Me3Ph L4 and 2,6‐Et2–4‐MePh L5 ) were prepared and characterized with FT‐IR and 1H/13C NMR spectroscopy as well as elemental analysis. The treatment of L1 – L5 with CrCl3·3THF affords the corresponding chromium chloride complexes (Cr1 – Cr5 ) in excellent yields. The molecular structures of Cr2 and Cr3 characterized by X‐ray diffraction show a distorted octahedral geometry with three nitrogen atoms and three chlorine atoms around the metal center. On activation with either MAO or MMAO, Cr1 – Cr5 collectively display high activity (up to 14.96 × 106 g (PE) mol−1 (Cr) h−1 at 60 °C) affording highly linear polyethylene with low molecular weight distribution (Mw/Mn) ranging from 1.06 to 2.81. An in‐depth catalytic evaluation of Cr1 was conducted in order to investigate how the cocatalyst type and its amount, reaction temperature and polymerization time affect the catalytic activities and polymer properties.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2020-01-09 | Applied Organometallic Chemistry |