A biphenylene-bridged dinuclear constrained geometry titanium complex for ethylene and ethylene/1-octene polymerizations

Lee, Min Hyung; Park, Myung Hwan; Sung, Woo Young; Kim, Seong Kyun; Son, A. van; Do, Youngkyu

doi:10.1016/j.jorganchem.2011.10.010

Cited by 4 publications

(3 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1-Hexene and 1-octene are widely used as co-monomers for high-quality polyolefin production. − The growing need for polyolefin products has resulted in the strong demand for 1-hexene and 1-octene. Moreover, the physical and mechanical properties of polyethylene products can be effectively improved by introducing 1-hexene and 1-octene monomers into a polyethylene chain backbone. , Currently, 1-hexene and 1-octene are mainly produced by ethylene oligomerization. In general, the non-selective ethylene oligomerization method mostly produces the oligomers with Schulz–Flory distribution, which require intensive energy to further separate the individual component from the mixture. − However, the ethylene tri/tetramerization method, which directly and selectively produces 1-hexene and 1-octene, has attracted considerable research interests from both academic and industrial communities. , …”

Section: Introductionmentioning

confidence: 99%

“…Moreover, the physical and mechanical properties of polyethylene products can be effectively improved by introducing 1-hexene and 1-octene monomers into a polyethylene chain backbone. 6 , 7 Currently, 1-hexene and 1-octene are mainly produced by ethylene oligomerization. In general, the non-selective ethylene oligomerization method mostly produces the oligomers with Schulz–Flory distribution, which require intensive energy to further separate the individual component from the mixture.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Chromium-Based Complexes Bearing Aminophosphine and Phosphine–Imine–Pyrryl Ligands for Selective Ethylene Tri/Tetramerization

Liu

Liu²,

Yang³

et al. 2023

ACS Omega

View full text Add to dashboard Cite

A series of Cr-based complexes 6−10 bearing aminophosphine (P,N) ligands Ph 2 P−L−NH 2 [L = CH 2 CH 2 (1), L = CH 2 CH 2 CH 2 (2), and L = C 6 H 4 CH 2 (3)] and phosphine−imine− pyrryl (P,N,N) ligands 2-(Ph 2 P−L−N�CH)C 4 H 3 NH [L = CH 2 CH 2 CH 2 ( 4) and L = C 6 H 4 CH 2 (5)] were prepared, and their catalytic properties were examined for ethylene tri/tetramerization. Xray crystallographic analysis of complex 8 indicated the κ 2 -P,N bidentate coordination mode at the Cr(III) center and the distorted octahedral geometry of monomeric P,N−CrCl 3 . Upon activation by methylaluminoxane (MAO), complexes 7−8 bearing P,N (PC 3 N backbone) ligands 2−3 showed good catalytic reactivity for ethylene tri/tetramerization. On the other hand, complex 6 bearing the P,N (PC 2 N backbone) ligand 1 was found active for non-selective ethylene oligomerization, while complexes 9−10 bearing P,N,N ligands 4−5 only produced polymerization products. In particular, the high catalytic activity of 458.2 kg/(g•Cr•h), excellent selectivity of 90.9% (1-hexene and 1-octene combined), and extremely low PE content of 0.1% were obtained with complex 7 in toluene at 45 °C and 45 bar. These results suggest that rational control of P,N and P,N,N ligand backbones, including a carbon spacer and rigidity of a carbon bridge, can lead to the high-performance catalyst for the ethylene tri/tetramerization process.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Chromium-Based Complexes Bearing Aminophosphine and Phosphine–Imine–Pyrryl Ligands for Selective Ethylene Tri/Tetramerization

Liu

Liu²,

Yang³

et al. 2023

ACS Omega

View full text Add to dashboard Cite

show abstract

“…Recently, the binuclear zirconium complexes with bidentate N‐(ortho‐dimethylaminobenzyl)anilide ligand were prepared by Liu et al, when activated with Al(i‐Bu) 3 and Ph 3 CB(C 6 F 5 ) 4 , these complexes produced ultra‐high molecular weight polyethylene or relatively high molecular weight poly(ethylene‐ co ‐1‐hexene) with reasonable 1‐hexene incorporation. Lee et al reported a biphenylene‐bridged dinuclear constrained geometry titanium complex for ethylene and ethylene/1‐octene polymerizations and found this catalytic system exhibits significantly increased molecular weight, as well as high activity and high 1‐octene incorporation in ethylene and ethylene/1‐octene polymerizations in comparison with the corresponding mononuclear CGC analogs. In 2012, Lee synthesized zirconium complexes containing fully deprotonated 2‐(2H‐benzo[d][1,2,3] triazol‐2‐yl) ‐4,6‐di‐ tert ‐pentylphenol and used as catalysts for the polymerization of ethylene with controlled bimodal molecular weight distribution.…”

Section: Introductionmentioning

confidence: 99%

Asymmetric binuclear metallocene complexes and their application for olefin polymerization

Huang

2013

J of Applied Polymer Sci

View full text Add to dashboard Cite

Asymmetric double silylene-bridged binuclear complexes [(g 5 -RC 5 H 4 )MCl 2 ] 2 [l, l-(SiMe 2 ) 2 (g 5 -t-BuC 5 H 2 )(g 5 -C 5 H 3 )] [R 5 H, M 5 Ti (1); R 5 Me, M 5 Ti (2); R 5 allyl, M 5 Ti(3); R 5 H, M 5 Zr (4); R 5 allyl, M5 Zr (6)]; and [(g 5 -C 5 H 5 )TiCl 2 ] 2 [l, l-(SiMe 2 ) 2 (g 5 -Me 3 SiC 5 H 2 )(g 5 -C 5 H 3 )] (5) were synthesized by the reaction of (g 5 -RC 5 H 4 ) TiCl 3 or (g 5 -RC 5 H 4 )ZrCl 3 ÁDME (R 5 H, allyl) with [l, l-(SiMe 2 ) 2 (g 5 -t-BuC 5 H 2 )(g 5 -C 5 H 3 )] Li 2 or [l, l-(SiMe 2 ) 2 (g 5 -Me 3 Si C 5 H 2 )(g 5 -C 5 H 3 )]Li 2 in THF, and they were all well characterized by 1 H NMR, MS, IR, and EA. When activated with methylaluminoxane (MAO), they are efficient catalysts for the polymerization of ethylene (Complex 4, 5.99 3 10 5 g-PE/molÁZrÁh) and the polymer with multipeak broaden molecular weight distribution (PD 5 Mw/Mn) was obtained (polymer sample gained by complex 3, PD 5 25.03). The copolymerization results indicate that 1-hexene could incorporate into the growing PE chain with these complexes in the presence of MAO (Complex 4, 1.07 3 10 6 g-PE/molÁZrÁh; 1-hexene content, 1.57% mol).

show abstract

Progress in the catalyst for ethylene/α‐olefin copolymerization at high temperature

Liu

2023

Can J Chem Eng

View full text Add to dashboard Cite

Ethylene/α‐olefin copolymers are one of the most widely‐used polyolefin materials. With the continuous improvement of polyolefin catalysts, high‐performance polyolefin materials were synthesized by adjusting the chain microstructure, changing the comonomer type and comonomer insertion amount, among which the ethylene/α‐olefin random copolymer elastomer (POE) and olefin block copolymer elastomer (OBC) are the most famous and well accepted by the market. The excellent properties of POE and OBC first depend on their polymer chain microstructure. The chain microstructure of polyolefins is fundamentally determined by the catalysts, polymerization conditions, comonomer feed policies, and reaction engineering. High‐performance ethylene/α‐olefin copolymer elastomers are currently prepared by high‐temperature solution polymerization process, which needs to be carried out at a temperature above the melting point of the polymer and is beneficial to speed up the polymerization reaction rate and control the polyolefin chain microstructure. However, the high‐temperature solution polymerization process launched more stringent requirements for the olefin coordination polymerization catalyst. Systematic reports on catalysts for high‐temperature solution copolymerization of ethylene and α‐olefins are lacking. In this review, we screened some catalysts suitable for the controllable copolymerization and high‐temperature solution copolymerization of ethylene/α‐olefin based on the catalyst's heat resistance, copolymerization activity, comonomer insertion ability, molecular weight, and distribution of the copolymer, including traditional Z–N catalysts, metallocene catalysts, and post‐metallocene catalysts. And the future development of catalysts for high‐temperature solution copolymerization of olefins, catalysts for precise control of polyolefin chain microstructures, and catalysts for olefin copolymerization with polar monomers at high temperature are envisaged.

show abstract

A biphenylene-bridged dinuclear constrained geometry titanium complex for ethylene and ethylene/1-octene polymerizations

Cited by 4 publications

References 44 publications

Chromium-Based Complexes Bearing Aminophosphine and Phosphine–Imine–Pyrryl Ligands for Selective Ethylene Tri/Tetramerization

Chromium-Based Complexes Bearing Aminophosphine and Phosphine–Imine–Pyrryl Ligands for Selective Ethylene Tri/Tetramerization

Asymmetric binuclear metallocene complexes and their application for olefin polymerization

Progress in the catalyst for ethylene/α‐olefin copolymerization at high temperature

Contact Info

Product

Resources

About