Synthesis of a new salphen‐type titanium complex and its application in ethylene polymerization and copolymerization

Abstract

TiCl 2 [salphen(di-tBu)] was synthesized, characterized and employed as pre-catalyst in ethylene homo-and copolymerization with propylene, 1-octene and 10-undecen-1-ol. X-ray diffraction study on the titanium complex revealed a distorted octahedral coordination of the central metal with a trans-Cl, cis-O, cis-N arrangement. The complex combined with MAO afforded moderate catalytic activities in ethylene polymerization. Furthermore the catalyst not only copolymerized ethylene with apolar monomer (propylene and 1-octene), but also possessed significant capability of incorporation with polar monomer (10-undecen-1-ol). Only single insertion of 1-octene unit in ethylene-co-1-octene polymer was detected by 13 C NMR spectrum.

FI Catalysts for Olefin Polymerization—A Comprehensive Treatment

“…As mentioned in section , those traditional Schiff base ligands such as salen and salphen tend to adopt the geometry cis -N/ cis -O/ trans -X with group 4 metals, ,,,,,− whereas in order for efficient olefin insertion to occur, the X ligands (potential reaction site) are preferably placed cis to each other.…”

“…Among the phenoxy−azo and phenoxy−imine chelating compounds, which Taylor screened for ethylene polymerization in conjunction with TiCl 4 /Et 2 AlCl (see section ), bridged phenoxy−imine ligands, salen, salpen, and salphen, were examined, but they were considered to be inactive (rather correctly in retrospect) . The investigation on group 4 metal complexes of salen, salpen, or salphen for olefin polymerization was resumed after a long pause in the late 1990s, which is compiled in Table . ,,,,,,,,,,, Repo and co-workers prepared a Zr salen complex, (L FI−FI )ZrCl 2 (thf) ( 314 ), and determined their solid state structures by X-ray crystallography, which revealed that the chlorides were trans to each other and the THF molecule occupied the seventh coordination site in the ONNO plane . The trans -Cl atoms of some Zr and Hf acen complexes were rearranged cis to each other upon removal of the THF molecule, however, the Zr salen complex exhibited similar low activities (120−130 g-polymer/(mmol-M·h) at 80 °C, 0.5 MPa) with and without the coordinated THF.…”

“…34 The investigation on group 4 metal complexes of salen, salpen, or salphen for olefin polymerization was resumed after a long pause in the late 1990s, which is compiled in Table 34. 125,169,176,178,197,209,225,228,234,361,547,548 Repo and co-workers prepared a Zr salen complex, (L FI-FI )ZrCl (thf) (314), and determined their solid state structures by X-ray crystallography, which revealed that the chlorides were trans to each other and the THF molecule occupied the seventh coordination site in the ONNO plane. 361 The trans-Cl atoms of some Zr and Hf acen complexes were rearranged cis to each other upon removal of the THF molecule, 546 however, the Zr salen complex exhibited similar low activities (120-130 g-polymer/(mmol-M 3 h) at 80 °C, 0.5 MPa) with and without the coordinated THF.…”

Design and synthesis of binuclear vanadium catalysts for copolymerization of ethylene and polar monomers

“…In addition, the M w values of the copolymer were extremely higher than the reported results. [36][37][38][39] In the differential scanning calorimetry (DSC) results of the obtained copolymers, the T m values decreased (Fig. 3).…”