Copolymerization of Ethylene with Vinyl Monomers using Heterogeneous Catalysts Consisting of α‐Diimine Ni(II) Complexes Immobilized into a Fluorotetrasilicic Mica Interlayer in the Presence of an Alkylaluminum Compound

Abstract

α‐Diimine nickel complexes immobilized into fluorotetrasilicic mica interlayers are prepared by the reaction of an α‐diimine ligand and nickel‐ion‐exchanged fluorotetrasilicic mica, and these are used for the copolymerization of ethylene with linear α‐olefins (1‐hexene, 1‐octene, and 1‐decene), cyclic olefins (norbornene and cyclopentene), or polar vinyl monomers (methyl acrylate and 5‐hexenenitrile). The copolymerization of ethylene with α‐olefins affords linear low‐density polyethylene including methyl and alkyl branches. The incorporation of cyclopentene into the main chain is proved by the 13C NMR spectrum of the ethylene/cyclopentene copolymer. No significant activity is observed during the copolymerization of ethylene with norbornene, methyl acrylate, or 5‐hexenenitrile.

Nickel(II) Complex Bearing Fluorine-substituted α-Diimine Ligand Immobilized in Fluorotetrasilicic Mica Interlayer as Heterogeneous Catalysts for Ethylene Oligomerization

“…The results of the ethylene oligomerization using the procatalyst L1/Ni 2 -mica have already been reported in a previous paper 55) . The procatalysts (L2-4/Ni 2 -mica) based on the com- plexes bearing the α-diimine ligands containing phenyl groups substituted by mono-or di-fluorine atoms showed a much higher activity for the ethylene oligomerization compared to the procatalyst (L1/Ni 2 -mica) based on the complex bearing no fluorine-substituted ligand L1.…”

“…Nickel ion-exchanged fluorotetrasilicic mica (Ni 2 -mica) was prepared according to a previous paper 55) . The physicochemical properties of the prepared Ni 2 -mica are summarized in Table 1.…”

Oligomerization of Ethylene to Produce Linear α-Olefins Using Heterogeneous Catalyst Prepared by Immobilization of α-Diiminenickel(II) Complex into Fluorotetrasilicic Mica Interlayer

“…The nickel ion-exchanged fluorotetrasilicic mica (Ni 2+ -Mica) was prepared by a method reported in a previous paper [20]. The dried Ni 2+ /Mica 0.25 g was weighed into a 20-mL Schlenk flask under a nitrogen atmosphere, and then the acetonitrile solution of the appropriate ligand (850 μmol-ligand for 1 g Ni 2+ -Mica) was added.…”