Group 4 permethylindenyl complexes for slurry-phase polymerisation of ethylene

Abstract

Supported group 4 permethylindenyl based catalysts displayed extremely high ethylene polymerisation activity affording popcorn shaped low molecular weights polyethylenes.

Slurry-phase ethylene polymerisation using group 4 ansa-bridged permethylindenyl complexes supported on polymethylaluminoxane

“…We recently reported a range of unsymmetrical ansabridged permethylindenyl compounds of the type Me 2 SB(Cp R ,I*)ZrX2 ({(η 5 -C9Me6)Me2Si(η 5 -C5H3R)}ZrX2; R = H, Me and n Bu; X = Cl, Br, Me and CH2Ph) and R 2 SB( tBu 2 Flu,I*)ZrX2 ({(η 5 -C9Me6)R2Si(η 5 -2,9-t Bu-C13H6)}ZrX2, {(η 5 -I*)R2Si(η 5 -2,9-t Bu-Flu)}ZrX2; R = Me, Et and X = Cl and Br) for slurry-phase ethylene polymerisation (Chart 1). [7,35,36] When immobilised on sMAO the species showed activities up to 83% higher than an industrial standard, (Cp nBu )2ZrCl2, under the same polymerisation conditions. [35]…”

“…[7,35,36] When immobilised on sMAO the species showed activities up to 83% higher than an industrial standard, (Cp nBu )2ZrCl2, under the same polymerisation conditions. [35]…”

“…[62] The crystallinities of the polymers produced using 3sMAO and 5sMAO were significantly lower than for the polymer produced using AsMAO (45, 57 and 75% respectively). This is expected based on the higher molecular weights of the polymers produced from 3sMAO and 5sMAO compared to AsMAO, [35] which can lead to more chain entanglements and hinder crystal formation and growth (Mw = 196, 160 and 76 kg mol −1 respectively at 80 °C). [53,54] 3LDHMAO displayed a peak polymerisation activity of 4747 kgPE molZr -1 h -1 bar -1 respectively at 70 °C; similar to that of 3sMAO (4191 kgPE molZr -1 h -1 bar -1 ) (Figure 10 and SEM analysis of the polyethylenes produced using 3LDHMAO showed the formation of aggregated, non-uniform polymer particles, mimicking the morphology of the solid support (Figure 11).…”

Ethylene Polymerization Using Zirconocenes Supported on Pentafluorophenyl-Modified Solid Polymethylaluminoxane

“…We recently reported a range of unsymmetrical ansabridged permethylindenyl compounds of the type Me 2 SB(Cp R ,I*)ZrX2 ({(η 5 -C9Me6)Me2Si(η 5 -C5H3R)}ZrX2; R = H, Me and n Bu; X = Cl, Br, Me and CH2Ph) and R 2 SB( tBu 2 Flu,I*)ZrX2 ({(η 5 -C9Me6)R2Si(η 5 -2,9-t Bu-C13H6)}ZrX2, {(η 5 -I*)R2Si(η 5 -2,9-t Bu-Flu)}ZrX2; R = Me, Et and X = Cl and Br) for slurry-phase ethylene polymerisation (Chart 1). [7,35,36] When immobilised on sMAO the species showed activities up to 83% higher than an industrial standard, (Cp nBu )2ZrCl2, under the same polymerisation conditions. [35] Chart 1.…”

“…[7,35,36] When immobilised on sMAO the species showed activities up to 83% higher than an industrial standard, (Cp nBu )2ZrCl2, under the same polymerisation conditions. [35] Chart 1. Example of previously reported group 4 permethylindenyl complexes Ind*(SiMe2)2Cl was synthesised in an analogous fashion to previously reported Ind*SiMe2Cl; [36] hexamethylindene (Ind # H) was deprotonated with 1.1 equivalents of n-butyllithium and the product added to 3.0 equivalents of Me4Si2Cl2.…”