Bis(benzothiazolyl) titanium, zirconium and vanadium complexes as catalysts for ethylene polymerization

Vanadium complexes bearing 8-anilide-5,6,7-trihydroquinoline ligands for ethylene (co-)polymerization

“…Vanadium catalysts play a very important role in the field of olefin coordination polymerization because they can be widely used in the synthesis of high molecular weight polyethylenes, cycloolefin copolymers, ethylene-propylene rubbers, and so on. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] However, high valent vanadium active species are easily reduced to low valent and low active species, especially at high temperatures. In order to solve this problem, chlorinated hydrocarbons or ethyltrichloroacetate (ETA) are added to the catalytic system as a reactivator to maintain the higher valence and higher activity of the vanadium active species.…”

Structure–property-relationship studies with ethylene polymerization catalysts of Ti, Zr and V containing heterocyclic ligands

“…Recently [1][2][3] we have shown that benzimidazoles, benzothiazoles and benzoxazoles can be applied as suitable ligands in titanium, zirconium and vanadium complexes that can be activated with methyalumoxane (MAO) and then be applied successfully for catalytic ethylene polymerization [4][5][6]. In spite of their hetero atoms and the oxophilicity of the metals, the performances of such catalysts are remarkable.…”

Mononuclear complexes with heterocyclic ligands as ethylene polymerization catalysts for single-reactor bimodal polyethylene technology

“…1,2-Bis-benzimidazoles and 2,6-bis(benzimidazolyl) pyridine are well known ligand precursors for transition metal complexes [14][15][16][17][18][19][20][21][22][23][24]. So far, for ethylene polymerization, 1,2-bis(benzimidazolyl) benzene copper [25], titanium, zirconium and vanadium complexes were reported [26][27][28] that can be activated with methyalumoxane (MAO) and then be applied successfully for catalytic ethylene polymerization. The vanadium complexes of bis(benzimidazole) amine tridentate ligands [N,N,N], are active ethylene polymerization catalysts after activation with alkylaluminum compounds [29] and 2,6-bis(2-benzimidazolyl) pyridine zirconium dichloride / MAO polymerizes methylacrylate [30].…”