Polystyrene supports for vanadium ethylene polymerisation catalysts

Chan, Michael C. W.; Chew, Kong Chin; Dalby, Christopher I.; Gibson, Vernon C.; Kohlmann, A.; Little, I. R.; Reed, Warren

doi:10.1039/a802656d

Cited by 71 publications

(43 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Increasing ligands denticity seems to be an efficient method to stabilize the active species of vanadium catalyst, which produced high molecular weights polymers with high catalytic activities 11–24. For example, Redshaw and coworkers reported that vanadium complexes with calixarene ligands exhibited excellent performance in olefin polymerization catalysis,11–16 Gibson and coworkers found tridentate bis(benzimidazole) amine ligand can stabilize the vanadium complexes that exhibited high activity toward ethylene (co)polymerization 17–19. Our group have synthesized and characterized a series of vanadium(V) complexes bearing tetradentate trihydroxy amine ligands, which exhibit high catalytic activities for the copolymerization of ethylene with some polar norbornene derivatives 20.…”

Section: Introductionmentioning

confidence: 99%

Ethylene homopolymerizaton and copolymerizaton by vanadium(III) complexes containing tridentate or tetradentate iminopyrrolyl ligands

Shi

2011

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

Iminopyrrolyl vanadium(III) complexes 2a–b bearing tridentate ligands [C4H3NCHNC6H4L]VCl2(THF) [L = 2‐P(C6H5)2 (2a), 2‐SMe (2b)] and complexes 2c–d with tetradentate ligands [(C4H3NCHN)2R]VCl(THF) [R = 1,2‐C6H4 (2c), 1,2‐C2H4 (2d)] have been synthesized in high yields. With diethylaluminium chloride as a cocatalyst, complexes 2a–d were investigated as efficient catalysts for ethylene polymerization under various reaction conditions, and exhibited high catalytic activity and remarkable thermal stability. With these complexes, high molecular weight polymers with unimodal molecular weight distributions were obtained, indicating that the polymerization reaction took place in a single‐site nature. Ethylene/1‐hexene copolymerizations were also investigated in the presence of Et2AlCl. Both increasing ligand denticity and introducing softer atom into the sidearm of the ligands significantly influenced catalytic activity, comonomer incorporation, and the molecular weights of the resultant polymers, suggesting that both the steric and the electronic effects of the ligands played an important role in adjusting chain propagation and transfer rate. The chain transfer mechanisms involved in the copolymerization process were investigated by carefully analyzing the microstructure of the copolymers. The signals of vinyl, disubstituted and tri‐substituted vinylene double bond end groups were detected in the copolymer obtained by 2a/Et2AlCl system but not in those by 2b–c/Et2AlCl systems, indicating that bulky electron‐donating group, P(C6H5)2, may lead to those unusual transfer reactions. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

show abstract

Section: Introductionmentioning

confidence: 99%

Ethylene homopolymerizaton and copolymerizaton by vanadium(III) complexes containing tridentate or tetradentate iminopyrrolyl ligands

Shi

2011

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

show abstract

“…However, this type of catalyst tends to be thermally unstable. In their study, a polystyrene support system was found to be effective for the stabilization of the active species for the ethylene polymerization and resulted in an improvement of the catalytic lifetime and activities 11. In this study, we synthesized several new alkylimido and arylimido vanadium complexes with cyclopentadinenyl ligands to investigate the substituent effect on their catalytic activity toward ethylene polymerization.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of pentavalent imidovanadium complexes and their catalyses for the polymerization of ethylene and propylene

Sato

Nakayama

Yasuda

2005

J of Applied Polymer Sci

View full text Add to dashboard Cite

Imidovanadium complexes with cyclopentadienyl (Cp) ligands-(Cp)V(ANC 6 H 4 Me-4)Cl 2 (1), (Cp)V(AN t Bu)Cl 2 (2), and ( t BuCp)V(AN t Bu)Cl 2 (3; t BuCp ϭ tert-butylcyclopentadienyl)-were synthesized through the reaction of imidovanadium trichloride with (trimethylsilyl)cyclopentadiene derivatives. The molecular structure of 3 was determined by X-ray crystallography. The monocyclopentadienyl complex 1 exhibited moderate activity in combination with methylaluminoxane [MAO; 10.3 kg of polyethylene (mol of V) Ϫ1 h Ϫ1 atm Ϫ1 ], whereas similar complexes with bulky t Bu groups, 2 and 3, were less active. (2-Methyl-8-quinolinolato)imidovanadium complexes, V(ANR)(OˆN)Cl 2 (R ϭ C 6 H 3 i Pr 2 -2,6 (4) or n-hexyl (5), OˆN ϭ 2-methyl-8-quinolinolato), were obtained from the reaction of imidovanadium trichloride with 2-methyl-8-quinolinol. Upon activation with modified MAO, complex 4 showed moderate activities for the polymerization of ethylene at room temperature. The complex 5/MAO system also exhibited moderate activity at 0°C. The polyethylenes obtained by these complexes had considerably high melting points, which indicated the formation of linear polyethylene. Moreover, the 5/dried MAO system showed propylene polymerization activities and produced polymers with considerably high molecular weights and narrow molecular weight distributions.

show abstract

“…[65] As a means of preventing such deactivation pathways Gibson et al prepared vanadium(V) imido complexes supported on polystyrene. [66] Attachment of the catalyst through the imido ligand was achieved by an imide-exchange reaction of a tert-butylimido compound with an amino-functionalised polystyrene (PS) resin. ) although a lower activity than for the corresponding homogeneous 2-methylphenylimido complex 17.…”

Section: Dedicated Cluster Reviewsmentioning

confidence: 99%

Transition Metal Imido Compounds as Ziegler–Natta Olefin Polymerisation Catalysts

2005

View full text Add to dashboard Cite

Dedicated to Professor Richard R. Schrock on the occasion of his 60 th birthday in appreciation of his many contributions to organometallic chemistry.Abstract: Transition metal imido compounds having the general formula [(L) n M(NR)] [where (L) n is a supporting ligand or ligand set, and R typically is alkyl or aryl] have been known for nearly 50 years, and during the last two decades have been the focus of considerable attention. Relatively recently their potential application in the Ziegler-Natta polymerisation of olefins has been realised. In this contribution we review the Ziegler-Natta polymerisation of olefins by transition metal imido compounds. A general introduction to homogeneous Ziegler-Natta olefin polymerisation and key aspects of transition metal imido chemistry is given, followed by a short description of a related imidobased polymerisation process, namely ring-opening olefin metathesis polymerisation catalysed by imidosupported molybdenum and tungsten alkylidenes. A summary of the "design principles" that have been employed in the development of certain imido-based Ziegler-Natta catalysts is presented, followed by a comprehensive survey of the literature in the title area.

show abstract

Polystyrene supports for vanadium ethylene polymerisation catalysts

Cited by 71 publications

References 14 publications

Ethylene homopolymerizaton and copolymerizaton by vanadium(III) complexes containing tridentate or tetradentate iminopyrrolyl ligands

Ethylene homopolymerizaton and copolymerizaton by vanadium(III) complexes containing tridentate or tetradentate iminopyrrolyl ligands

Synthesis of pentavalent imidovanadium complexes and their catalyses for the polymerization of ethylene and propylene

Transition Metal Imido Compounds as Ziegler–Natta Olefin Polymerisation Catalysts

Contact Info

Product

Resources

About