Ethylene polymerization activity under practical conditions displayed by zirconium complexes having two phenoxy-imine chelate ligands

Matsukawa, Naoto; Matsui, Shigekazu; Mitani, Makoto; Saito, Junji; Tsuru, K.; Kashiwa, Norio; Fujita, Terunori

doi:10.1016/s1381-1169(01)00050-4

Cited by 99 publications

(49 citation statements)

References 14 publications

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“…Thus, to strengthen the metalligand bonds of complex 1, electron-donating groups were introduced at the para-positions of phenyl groups which would have a large electronic influence on the zirconium metal while polymerization sites were retained in the same steric environment. [21] As expected, the activity ratio of 75 8C to 50 8C (A 75 /A 50 ) was improved from 0.18 (R 1 phenyl) to 0.61 (R 1 4-MeO-phenyl), 0.45 (R 1 4-Me 2 N-phenyl) and 0.67 (R 3 MeO) ( Figure 5). …”

Section: Reviewssupporting

confidence: 77%

FI Catalysts: A New Family of High Performance Catalysts for Olefin Polymerization

Makio

Kashiwa

Fujita

2002

Advanced Synthesis & Catalysis

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416

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This paper reviews a new family of olefin polymerization catalysts. The catalysts, named FI catalysts, are based on non‐symmetrical phenoxyimine chelate ligands combined with group 4 transition metals and were developed using “ligand‐oriented catalyst design”. FI catalysts display very high ethylene polymerization activities under mild conditions. The highest activity exhibited by a zirconium FI catalyst reached an astonishing catalyst turnover frequency (TOF) of 64,900 s –1 atm –1, which is two orders of magnitude greater than that seen with Cp2ZrCl2 under the same conditions. In addition, titanium FI catalysts with fluorinated ligands promote exceptionally high‐speed, living ethylene polymerization and can produce monodisperse high molecular weight polyethylenes (Mw/Mn<1.2, max. Mn>400,000) at 50 °C. The maximum TOF, 24,500 min –1 atm –1, is three orders of magnitude greater than those for known living ethylene polymerization catalysts. Moreover, the fluorinated FI catalysts promote stereospecific room‐temperature living polymerization of propylene to provide highly syndiotactic monodisperse polypropylene (max. [rr] 98%). The versatility of the FI catalysts allows for the creation of new polymers which are difficult or impossible to prepare using group 4 metallocene catalysts. For example, it is possible to prepare low molecular weight (Mv∼103) polyethylene or poly(ethylene‐co‐propylene) with olefinic end groups, ultra‐high molecular weight polyethylene or poly(ethylene‐co‐propylene), high molecular weight poly(1‐hexene) with atactic structures including frequent regioerrors, monodisperse poly(ethylene‐co‐propylene) with various propylene contents, and a number of polyolefin block copolymers [e.g., polyethylene‐b‐poly(ethylene‐co‐propylene), syndiotactic polypropylene‐b‐poly(ethylene‐co‐propylene), polyethylene‐b‐poly(ethylene‐co‐propylene)‐b‐syndiotactic polypropylene]. These unique polymers are anticipated to possess novel material properties and uses.

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Section: Reviewssupporting

confidence: 77%

FI Catalysts: A New Family of High Performance Catalysts for Olefin Polymerization

Makio

Kashiwa

Fujita

2002

Advanced Synthesis & Catalysis

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416

286

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“…via transfer to aluminium from MAO) causes catalyst death, then this steric modification would not be expected to make a significant difference. We note the growing body of evidence for the latter picture, such as the relatively poor polymerising capabilities of mono-salicylaldimine complexes [19] and improved stability of more electron-rich phenolate systems [20].…”

Section: Discussionmentioning

confidence: 91%

Radical and migratory insertion reaction mechanisms in Schiff base zirconium alkyls

Knight

Clarkson

Hammond

et al. 2005

Journal of Organometallic Chemistry

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“…16; the catalyst name ''FI'' comes from the Japanese pronunciation of the ligand '' À Fenokishi-À Imin'') display strikingly high activity when activated with MAO. [11][12][13][72][73][74] This activity corresponds to a catalyst turnover frequency (TOF) of 64 900 s À1 atm À1 , which is two orders of magnitude greater than that for Cp 2 ZrCl 2 with MAO. The highest activity displayed by FI catalyst 15 (Fig.…”

Section: Phenoxy-imine Ligated Early Transition Metal Complexes: Fi Cmentioning

confidence: 95%

High-performance olefin polymerization catalysts discovered on the basis of a new catalyst design concept

2008

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This critical review highlights the "ligand oriented catalyst design concept", a new catalyst design concept for olefin polymerization that has led to the development of high-activity catalysts. The concept has created a series of highly active ethylene polymerization catalysts, many of which show high activities comparable to those of group 4 metallocene catalysts. Moreover, these catalysts display unique polymerization catalysis to produce a wide variety of polymers that possess unprecedented molecular architectures that are either difficult or impossible to achieve using conventional catalysts (98 references).

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Ethylene polymerization activity under practical conditions displayed by zirconium complexes having two phenoxy-imine chelate ligands

Cited by 99 publications

References 14 publications

FI Catalysts: A New Family of High Performance Catalysts for Olefin Polymerization

FI Catalysts: A New Family of High Performance Catalysts for Olefin Polymerization

Radical and migratory insertion reaction mechanisms in Schiff base zirconium alkyls

High-performance olefin polymerization catalysts discovered on the basis of a new catalyst design concept

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