Symmetric and Asymmetric Binuclear α-Diimine Nickel(II) Complexes for Ethylene Polymerization

A series of symmetric and asymmetric binuclear α-diimine nickel(II) complexes toward ethylene polymerization were successfully synthesized and characterized by 1HNMR. All the catalysts were typically activated with MAO and displayed good activity at room temperature under 1atm ethylene pressure. The symmetric catalyst containing isopropyl on ligand-activated with 500 equiv MAO produced high molecular weight polyethylene with a PDI=1.75, while the symmetric catalyst containing methyl on ligand produced relatively low molecular weight polyethylene with a PDI=1.74. By contrast, the molecular weight, branching density of resultant polymer produced by asymmetric catalyst decrease roughly somewhere between that of polymers prepared by two symmetric catalysts.

[1]  Richard A. Collins,et al.  Monometallic and Bimetallic Titanium κ1-Amidinate Complexes as Olefin Polymerization Catalysts , 2017 .

[2]  Yun-peng Zhu,et al.  Dinuclear α‐Diimine NiII and PdII Complexes that Catalyze Ethylene Polymerization and Copolymerization , 2017 .

[3]  B. Long,et al.  Redox-Active Ligands: An Advanced Tool To Modulate Polyethylene Microstructure. , 2016, Journal of the American Chemical Society.

[4]  Lihua Guo,et al.  Palladium and Nickel Catalyzed Chain Walking Olefin Polymerization and Copolymerization , 2016 .

[5]  Wen‐Hua Sun,et al.  Ethylene polymerization by 2,3-diiminobutylnickel bromide pre-catalysts bearing remote benzhydryl substituents , 2015 .

[6]  Danfeng Zhang,et al.  Nickel cyclopentadienyl complexes as catalysts for ethylene polymerization , 2015 .

[7]  Yue-sheng Li,et al.  Neutral Nickel Catalysts for Olefin Homo- and Copolymerization: Relationships between Catalyst Structures and Catalytic Properties. , 2015, Chemical reviews.

[8]  Changle Chen,et al.  Highly Robust Palladium(II) α-Diimine Catalysts for Slow-Chain-Walking Polymerization of Ethylene and Copolymerization with Methyl Acrylate. , 2015, Angewandte Chemie.

[9]  Qing-Shan Li,et al.  Synthesis and application of α -diimine Ni(II) and Pd(II) complexes with bulky steric groups to polymerization of ethylene and methyl methacrylate , 2015 .

[10]  L. Qingquan,et al.  Synthesis of a novel branched–hyperbranched diblock polyolefin via chain walking and chain transfer polymerization from ethylene alone , 2015 .

[11]  O. Daugulis,et al.  Living Polymerization of Ethylene and Copolymerization of Ethylene/Methyl Acrylate Using “Sandwich” Diimine Palladium Catalysts , 2015 .

[12]  Ian A. Tonks,et al.  Analysis of Polymeryl Chain Transfer Between Group 10 Metals and Main Group Alkyls during Ethylene Polymerization , 2014 .

[13]  Qingquan Liu,et al.  A Novel Branched–Hyperbranched Block Polyolefin Produced via Chain Shuttling Polymerization from Ethylene Alone , 2014 .

[14]  K. Osakada,et al.  Ethylene Polymerization at High Temperatures Catalyzed by Double-Decker-Type Dinuclear Iron and Cobalt Complexes: Dimer Effect on Stability of the Catalyst and Polydispersity of the Product , 2014 .

[15]  K. Osakada,et al.  Dipalladium catalyst for olefin polymerization: introduction of acrylate units into the main chain of branched polyethylene. , 2014, Angewandte Chemie.

[16]  T. Marks,et al.  Very large cooperative effects in heterobimetallic titanium-chromium catalysts for ethylene polymerization/copolymerization. , 2014, Journal of the American Chemical Society.

[17]  Qing-Shan Li,et al.  New nickel(II) diimine complexes bearing phenyl and sec‐phenethyl groups: synthesis, characterization and ethylene polymerization behaviour , 2014 .

[18]  B. Long,et al.  Enhancing α-Diimine Catalysts for High-Temperature Ethylene Polymerization , 2014 .

[19]  Wen‐Hua Sun,et al.  Biphenyl-bridged 6-(1-aryliminoethyl)-2-iminopyridylcobalt complexes: Synthesis, characterization and ethylene polymerization behavior , 2014 .

[20]  B. Long,et al.  A robust Ni(II) α-diimine catalyst for high temperature ethylene polymerization. , 2013, Journal of the American Chemical Society.

[21]  Weibing Xu,et al.  Chiral Naphthyl-α-diimine Nickel(II) Catalysts Bearing sec-Phenethyl Groups: Chain-Walking Polymerization of Ethylene at High Temperature and Stereoselective Polymerization of Methyl Methacrylate at Low Temperature , 2013 .

[22]  Shihui Li,et al.  Binuclear Rare-Earth-Metal Alkyl Complexes Ligated by Phenylene-Bridged β-Diketiminate Ligands: Synthesis, Characterization, and Catalysis toward Isoprene Polymerization , 2013 .

[23]  T. Agapie,et al.  Bimetallic coordination insertion polymerization of unprotected polar monomers: copolymerization of amino olefins and ethylene by dinickel bisphenoxyiminato catalysts. , 2013, Journal of the American Chemical Society.

[24]  Qing Wu,et al.  Substituent Effects of the Backbone in α-Diimine Palladium Catalysts on Homo- and Copolymerization of Ethylene with Methyl Acrylate , 2012 .

[25]  Jean-Christophe Daigle,et al.  Probing the Regiochemistry of Acrylate Catalytic Insertion Polymerization via Cyclocopolymerization of Allyl Acrylate and Ethylene. , 2012, ACS macro letters.

[26]  T. Agapie,et al.  Bimetallic effects on ethylene polymerization in the presence of amines: inhibition of the deactivation by Lewis bases. , 2012, Journal of the American Chemical Society.

[27]  T. Marks,et al.  Multinuclear olefin polymerization catalysts. , 2011, Chemical reviews.

[28]  Yulai Zhao,et al.  The synthesis of modified polyethylene via coordination polymerization followed by ATRP, RAFT, NMRP or ROP , 2010 .

[29]  Peng Xiang,et al.  Hyperbranched-Linear Polyethylene Block Polymers Constructed with Chain Blocks of Hybrid Chain Topologies via One-Pot Stagewise Chain Walking Ethylene Living Polymerization , 2010 .

[30]  Qi Wang,et al.  Selective activation of metallic center in heterobinuclear cobalt and nickel complex in ethylene polymerization , 2010 .

[31]  Ying Xu,et al.  Thermostable α-Diimine Nickel(II) Catalyst for Ethylene Polymerization: Effects of the Substituted Backbone Structure on Catalytic Properties and Branching Structure of Polyethylene , 2009 .

[32]  Shiping Zhu,et al.  Topology-Engineered Hyperbranched High-Molecular-Weight Polyethylenes as Lubricant Viscosity-Index Improvers of High Shear Stability , 2007 .

[33]  B. Rieger,et al.  Novel Non-Symmetric Nickel-Diimine Complexes for the Homopolymerization of Ethene: Control of Branching by Catalyst Design , 2002 .

[34]  Maurice Brookhart,et al.  New Pd(II)- and Ni(II)-Based Catalysts for Polymerization of Ethylene and .alpha.-Olefins , 1995 .