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Yue Q, Gao R, Song Z, Gou Q. Recent Advancements in the Synthesis of Ultra-High Molecular Weight Polyethylene via Late Transition Metal Catalysts. Polymers (Basel) 2024; 16:1688. [PMID: 38932038 PMCID: PMC11207456 DOI: 10.3390/polym16121688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Revised: 06/01/2024] [Accepted: 06/05/2024] [Indexed: 06/28/2024] Open
Abstract
Ultra-high molecular weight polyethylenes (UHMWPEs) are significant engineering plastics for their unique properties, such as high impact resistance, abrasion resistance, weatherability, lubricity, and chemical resistance. Consequently, developing a suitable catalyst is vital in facilitating the preparation of UHMWPE. The late transition metal catalysts have emerged as effective catalysts in producing UHMWPE due to their availability, enhanced tolerance to heteroatom groups, active polymerization characteristics, and good copolymerization ability with polar monomers. In this review, we mainly focus on the late transition metal catalysts, summarizing advancements in their application over the past decade. Four key metals (Ni, Pd, Fe, Co) for generating linear or branched UHMWPE will be primarily explored in this manuscript.
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Affiliation(s)
- Qiang Yue
- Department of Polyethylene, SINOPEC (Beijing) Research Institute of Chemical Industry Co., Ltd., Beijing 100013, China
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2
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Wang Y, Lai J, Gao R, Gou Q, Li B, Zheng G, Zhang R, Yue Q, Song Z, Guo Z. Recent Advances in Nickel Catalysts with Industrial Exploitability for Copolymerization of Ethylene with Polar Monomers. Polymers (Basel) 2024; 16:1676. [PMID: 38932025 PMCID: PMC11207433 DOI: 10.3390/polym16121676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Revised: 05/22/2024] [Accepted: 05/23/2024] [Indexed: 06/28/2024] Open
Abstract
The direct copolymerization of ethylene with polar monomers to produce functional polyolefins continues to be highly appealing due to its simple operation process and controllable product microstructure. Low-cost nickel catalysts have been extensively utilized in academia for the synthesis of polar polyethylenes. However, the development of high-temperature copolymerization catalysts suitable for industrial production conditions remains a significant challenge. Classified by the resultant copolymers, this review provides a comprehensive summary of the research progress in nickel complex catalyzed ethylene-polar monomer copolymerization at elevated temperatures in the past five years. The polymerization results of ethylene-methyl acrylate copolymers, ethylene-tert-butyl acrylate copolymers, ethylene-other fundamental polar monomer copolymers, and ethylene-special polar monomer copolymers are thoroughly summarized. The involved nickel catalysts include the phosphine-phenolate type, bisphosphine-monoxide type, phosphine-carbonyl type, phosphine-benzenamine type, and the phosphine-enolate type. The effective modulation of catalytic activity, molecular weight, molecular weight distribution, melting point, and polar monomer incorporation ratio by these catalysts is concluded and discussed. It reveals that the optimization of the catalyst system is mainly achieved through the methods of catalyst structure rational design, extra additive introduction, and single-site catalyst heterogenization. As a result, some outstanding catalysts are capable of producing polar polyethylenes that closely resemble commercial products. To achieve industrialization, it is essential to further emphasize the fundamental science of high-temperature copolymerization systems and the application performance of resultant polar polyethylenes.
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Affiliation(s)
- Ying Wang
- Department of Polyethylene, SINOPEC (Beijing) Research Institute of Chemical Industry Co., Ltd., Beijing 100013, China; (J.L.); (R.G.); (Q.G.); (B.L.); (G.Z.); (R.Z.); (Q.Y.); (Z.S.)
| | | | | | | | | | | | | | | | | | - Zifang Guo
- Department of Polyethylene, SINOPEC (Beijing) Research Institute of Chemical Industry Co., Ltd., Beijing 100013, China; (J.L.); (R.G.); (Q.G.); (B.L.); (G.Z.); (R.Z.); (Q.Y.); (Z.S.)
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3
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Dai J, Dai S. Impact of o-aryl halogen effects on ethylene polymerization: steric vs. electronic effects. Dalton Trans 2024; 53:9286-9293. [PMID: 38712871 DOI: 10.1039/d4dt00850b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Ligand steric hindrance and electronic effects play a crucial role in late-transition metal-catalyzed olefin polymerization. In this research, a series of o-aryl halogenated α-diimine ligands bearing bulky dibenzhydryl substituents, along with their corresponding nickel catalysts, have been synthesized and thoroughly characterized. The nickel catalysts demonstrated very high activity in ethylene polymerization, achieving a high rate of up to 107 g mol-1 h-1. The produced polyethylenes displayed a broad spectrum of molecular weights (12.2-871.7 kg mol-1) but maintained consistent branching densities (50-82/1000 C) when polymerized at a fixed temperature with different nickel catalysts. Notably, the polymerization temperature has a significant influence on both the molecular weight and branching density of the resulting polyethylene. Higher temperatures led to the formation of polyethylenes with lower molecular weights and increased branching densities. Interestingly, the o-aryl halogens significantly impact the molecular weight of the polyethylene. The size of the halogen substituents primarily determines the molecular weight of the polyethylene. However, in terms of branching density, the steric and electronic effects of these substituents appear to counteract each other. In addition, the branched high molecular weight polyethylenes from the bromine and chlorine substituted nickel catalysts are excellent polyethylene thermoplastic elastomers with high strain at break values (688-2478%) and high strain recovery values (42-62%).
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Affiliation(s)
- Jianjian Dai
- Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui, 230601, China.
| | - Shengyu Dai
- Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui, 230601, China.
- Anhui Laboratory of Molecule-Based Materials, Key Laboratory of Functional Molecular Solids, Ministry of Education, School of Chemistry and Materials Science, Anhui Normal University, Wuhu 241002, China
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Lu Z, Ge Y, Dai S. Flexible Axial Shielding Strategy for Improving Ethylene (Co)polymerization with 8-Cycloalkylnaphthyl α-Diimine Catalysts. Inorg Chem 2023; 62:14888-14895. [PMID: 37668508 DOI: 10.1021/acs.inorgchem.3c01568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/06/2023]
Abstract
8-aryl or alkyl-naphthyl substituents are widely used as an effective axial shielding strategy for the suppression of chain transfer in late-transition metal-catalyzed ethylene (co)polymerization to yield high molecular weight polyethylene and copolymers. In this study, two 8-cycloalkylnaphthyl acenaphthene-based α-diimine ligands and the corresponding four nickel and palladium complexes were designed and synthesized to explore the effect of axial flexible shielding on ethylene (co)polymerization. In ethylene polymerization, the nickel complexes displayed high activities (up to 1.99 × 106 g mol-1 h-1) and generated lightly branched (34-54/1000 C) polyethylenes with high molecular weights (up to Mn = 1075 kg/mol), whereas the corresponding palladium complexes exhibited moderate activities (level of 104 g mol-1 h-1), producing highly branched (111-125/1000 C) polyethylenes with high molecular weights (up to Mn = 37.6 kg/mol). Highly branched (110-123/1000 C) E-MA copolymers with moderate insertion ratios (1.97-5.56 mol %) were produced by these palladium complexes in ethylene/methyl acrylate (MA) copolymerization. In addition, the size of the 8-cycloalkyl ring in these α-diimine catalysts strongly influences the ethylene (co)polymerization. Compared to cyclopentyl groups, cyclohexyl groups are more effective in suppressing chain transfer reactions in the polymerization of ethylene and the copolymerization of ethylene and MA, leading to higher molecular weight polyethylene and E-MA copolymers. Most interestingly, compared to the reported rigid planar 8-arylnaphthyl catalysts, the flexible 8-cyclohexylnaphthyl catalysts exhibited higher activity and produced higher molecular weight polyethylene in ethylene polymerization. Moreover, in nickel-catalyzed ethylene polymerization, the cyclohexyl catalyst produced significantly reduced branched polyethylene, while in palladium-catalyzed ethylene (co)polymerization, the cyclohexyl catalyst produced more highly branched polyethylene and copolymers. In contrast to the previously reported flexible 8-butylnaphthyl nickel catalysts, the 8-cycloalkylnaphthyl catalysts reported in this work yielded polyethylene with narrow unimodal molecular weight distributions.
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Affiliation(s)
- Zhou Lu
- Anhui Laboratory of Molecule-Based Materials, Key Laboratory of Functional Molecular Solids, Ministry of Education, School of Chemistry and Materials Science, Anhui Normal University, Wuhu 241002, China
| | - You Ge
- Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, China
| | - Shengyu Dai
- Anhui Laboratory of Molecule-Based Materials, Key Laboratory of Functional Molecular Solids, Ministry of Education, School of Chemistry and Materials Science, Anhui Normal University, Wuhu 241002, China
- Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, China
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Wang YB, Nan C, Zhuo W, Zou C, Jiang H, Hao XQ, Chen C, Song MP. Amine-Imine Nickel Catalysts with Pendant O-Donor Groups for Ethylene (Co)Polymerization. Inorg Chem 2023; 62:5105-5113. [PMID: 36933227 DOI: 10.1021/acs.inorgchem.2c04240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
Abstract
The introduction of a secondary interaction is an efficient strategy to modulate transition-metal-catalyzed ethylene (co)polymerization. In this contribution, O-donor groups were suspended on amine-imine ligands to synthesize a series of nickel complexes. By adjusting the interaction between the nickel metal center and the O-donor group on the ligands, these nickel complexes exhibited high activities for ethylene polymerization (up to 3.48 × 106 gPE·molNi-1·h-1) with high molecular weight up to 5.59 × 105 g·mol-1 and produced good polyethylene elastomers (strain recovery (SR) = 69-81%). In addition, these nickel complexes can catalyze the copolymerization of ethylene with vinyl acetic acid, 6-chloro-1-hexene, 10-undecylenic, 10-undecenoic acid, and 10-undecylenic alcohol to prepare the functionalized polyolefins.
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Affiliation(s)
- Yan-Bing Wang
- College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, P. R. China
| | - Chenlong Nan
- College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, P. R. China
| | - Weize Zhuo
- College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, P. R. China
| | - Chen Zou
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Hui Jiang
- College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, P. R. China
| | - Xin-Qi Hao
- College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, P. R. China
| | - Changle Chen
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Mao-Ping Song
- College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, P. R. China
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6
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Peng D, Xu M, Tan C, Chen C. Emulsion Polymerization Strategy for Heterogenization of Olefin Polymerization Catalysts. Macromolecules 2023. [DOI: 10.1021/acs.macromol.3c00261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
Affiliation(s)
- Dan Peng
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Menghe Xu
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Chen Tan
- Institute of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui 230601, China
| | - Changle Chen
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
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7
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Ullah Khan W, Mazhar H, Shehzad F, Al-Harthi MA. Recent Advances in Transition Metal-Based Catalysts for Ethylene Copolymerization with Polar Comonomer. CHEM REC 2023; 23:e202200243. [PMID: 36715494 DOI: 10.1002/tcr.202200243] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 01/18/2023] [Indexed: 01/31/2023]
Abstract
The synthesis of polar functionalized polyolefin (PFP) offers improvement in mixing properties, polymer surface, and rheological properties with the potential of upgraded polyolefins for modern and ingenious applications. The synthesis of PFP from metal-based catalyzed olefin (non-polar in nature) copolymerization with polar comonomers embodies energy-efficient, atom-efficient, and apparently an upfront methodology. Despite their outstanding success during conventional polymerization of olefin, 3rd and 4th group (early transition metal)-based catalysts, owing to their electrophilic nature, face challenges mainly due to Lewis basic sites of the polar monomers. On the contrary, late transition metal-based catalysts have also made progress, in recent years, for PFP synthesis. The recent past has also witnessed several advancements in the development of dominating palladium-based catalysts while their lower resistance towards ligand functional groups has limited the practical application of abundant and cheaper nickel-based catalysts. However, the relentless efforts of the scientific community, during the past half-decade, have indicated rigorous progress in the development of nickel-based catalysts for PFP synthesis. In this review, we have abridged the recent research trends in both early as well as late transition metal-based catalyst development. Furthermore, we have highlighted the role of transition metal-based catalysts in influencing the polymer properties.
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Affiliation(s)
- Wasim Ullah Khan
- Interdisciplinary Research Center for Refining & Advanced Chemicals, Research Institute, King Fahd University of Petroleum & Minerals, Dhahran, 31261, Saudi Arabia
| | - Hassam Mazhar
- Department of Chemical Engineering, King Fahd University of Petroleum and Minerals, Dhahran, 31261, Saudi Arabia
| | - Farrukh Shehzad
- Department of Chemical Engineering, King Fahd University of Petroleum and Minerals, Dhahran, 31261, Saudi Arabia
| | - Mamdouh A Al-Harthi
- Interdisciplinary Research Center for Refining & Advanced Chemicals, Research Institute, King Fahd University of Petroleum & Minerals, Dhahran, 31261, Saudi Arabia.,Department of Chemical Engineering, King Fahd University of Petroleum and Minerals, Dhahran, 31261, Saudi Arabia
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8
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Wang H, Lu W, Bi H, Dai S. Dibenzosuberyl substituents suppressing chain transfer in Bis(imino)pyridyl Iron(II) catalyzed ethylene polymerization. POLYMER 2023. [DOI: 10.1016/j.polymer.2023.125868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
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9
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Wang H, Lu W, Zou M, Dai S. Direct Synthesis of Polyethylene Thermoplastic Elastomers Using Hybrid Bulky Acenaphthene-Based α-Diimine Ni(II) Catalysts. Molecules 2023; 28:molecules28052266. [PMID: 36903510 PMCID: PMC10005668 DOI: 10.3390/molecules28052266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 02/20/2023] [Accepted: 02/22/2023] [Indexed: 03/05/2023] Open
Abstract
Recently, polyolefin thermoplastic elastomers can be obtained directly using ethylene as a single feedstock via α-diimine nickel-catalyzed ethylene chain walking polymerization. Here, a new range of bulky acenaphthene-based α-diimine nickel complexes with hybrid o-phenyl and -diarylmethyl anilines were constructed and applied to ethylene polymerization. All the nickel complexes under the activation of excess Et2AlCl exhibited good activity (level of 106 g mol-1 h-1) and produced polyethylene with high molecular weight (75.6-352.4 kg/mol) as well as proper branching densities (55-77/1000C). All the branched polyethylenes obtained exhibited high strain (704-1097%) and moderate to high stress (7-25 MPa) at break values. Most interestingly, the polyethylene produced by the methoxy-substituted nickel complex exhibited significantly lower molecular weights and branching densities, as well as significantly poorer strain recovery values (48% vs. 78-80%) than those by the other two complexes under the same conditions.
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Affiliation(s)
- Hui Wang
- School of Chemistry and Chemical Engineering, Hefei Normal University, Hefei 230061, China
| | - Weiqing Lu
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu 241000, China
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
| | - Mingmin Zou
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
| | - Shengyu Dai
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu 241000, China
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
- Correspondence: ; Tel.: +86-13955189794
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Fumoto T, Tanaka R, Ooyama Y. Aggregation-induced emission of a bis(imino)acenaphthene zinc complex with tetraphenylethene units. Dalton Trans 2023; 52:5047-5055. [PMID: 36807366 DOI: 10.1039/d2dt03525a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Using bis(imino)acenaphthene (BIAN) zinc(II) and palladium(II) complexes with tetraphenylethene (TPE) units as bulky aryl groups, Zn-2 and Pd-2 have been designed and developed, and their photophysical properties in solution and in the solid state have been investigated. Both in solution and in the solid state Zn-2 and Pd-2 show two photoabsorption bands in the ranges of 300 nm to 350 nm and 450 nm to 600 nm, which are assigned to the π-π* transition originating from both the TPE units and naphthalene units and the intraligand charge transfer (ILCT) between the TPE units and the BIAN unit, respectively. Density functional theory (DFT) calculations demonstrated that for Zn-2 the highest occupied molecular orbitals (HOMO) are localized on the TPE units, while the lowest unoccupied molecular orbitals (LUMO) are localized on the BIAN unit, leading to the appearance of a photoabsorption band on the ILCT. The emission from Zn-2 was quenched in solution, but appeared as phosphorescence at around 600 nm by photoexcitation at the ILCT band in the solid state as well as in the aggregated state, which was formed by the addition of n-hexane as a poor solvent to the dichloromethane (DCM) solution. The aggregate formation of Zn-2 in the DCM/n-hexane (10 wt%/90 wt%) solution was confirmed by the Tyndall scattering and scanning electron microscopy (SEM) measurements, demonstrating the aggregation-induced emission (AIE) characteristics of Zn-2. On the other hand, Pd-2 was non-emissive in the solid state and in the aggregated state as well as in solution. Moreover, the DCM-inclusion complexes of Zn-2 and Pd-2 were obtained and their photophysical properties were investigated. It was found that the photoluminescence quantum yield (ΦPL-solid) values of Zn-2 and Zn-2-DCM in the solid state are less than 1%. Single-crystal X-ray structural analysis of Zn-2-DCM revealed the absence of intermolecular π-π interactions. Consequently, it was suggested that the low ΦPL-solid value of Zn-2 is mainly due to the radiationless relaxation of the excitons by dynamic rotation of the phenyl groups of the TPE units, even in the solid state and in the aggregation state.
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Affiliation(s)
- Takuma Fumoto
- Applied Chemistry Program, Graduate School of Advanced Science and Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima 739-8527, Japan.
| | - Ryo Tanaka
- Applied Chemistry Program, Graduate School of Advanced Science and Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima 739-8527, Japan.
| | - Yousuke Ooyama
- Applied Chemistry Program, Graduate School of Advanced Science and Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima 739-8527, Japan.
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New Ni(II)-Ni(II) Dinuclear Complex, a Resting State of the (α-diimine)NiBr2/AlMe3 Catalyst System for Ethylene Polymerization. Catalysts 2023. [DOI: 10.3390/catal13020333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
A novel room-temperature stable diamagnetic nickel complex 2 was detected upon activation of Brookhart-type ethylene polymerization pre-catalyst LNiBr2 (1, L = 1,4-bis-2,4,6-trimethylphenyl-2,3-dimethyl-1,4-diazabuta-1,3-diene) with AlMe3. Using in situ 1H, 2H, and 13C NMR spectroscopy, as well as DFT calculations, this species has been identified as an antiferromagnetically coupled homodinuclear complex [LNiII(μ-Me)(μ-CH2)NiIIL]+Br−. Its behavior in the reaction solution is characteristic of the resting state of nickel catalyzed ethylene polymerization.
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Sun H, Fan H, Zhu C, Zou W, Dai S. Direct Synthesis of Partially Chain-Straightened Propylene Oligomers and P-MA Co-Oligomers Using Axially Flexible Shielded Iminopyridyl Palladium Complexes. Polymers (Basel) 2022; 15:111. [PMID: 36616461 PMCID: PMC9823751 DOI: 10.3390/polym15010111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 12/15/2022] [Accepted: 12/22/2022] [Indexed: 12/29/2022] Open
Abstract
In this study, a series of partially chain-straightened propylene oligomers and functional propylene−methyl acrylate (P-MA) co-oligomers were synthesized with 8-alkyl-iminopyridyl Pd(II) catalysts. The molecular weight and polar monomer incorporation ratio could be tuned by using Pd(II) catalysts with various 8-alkyl-naphthyl substituents (8-alkyl: H, Me, and n-Bu). In propylene oligomerization, all the 8-alkyl-iminopyridyl Pd(II) catalysts convert propylene to partially chain-straightened (119−136/1000 C) oligomers with low molecular weights (0.3−1.5 kg/mol). Among the catalysts, Pd1 with non-substituent (H) on the ligand showed the highest activity of 5.4 × 104 g/((mol of Pd) h), generating oligomers with the lowest molecular weight (Mn: 0.3 kg/mol). Moreover, polar-functionalized propylene-MA co-oligomers with very high incorporation ratios (22.8−36.5 mol %) could be obtained in the copolymerization using these 8-alkyl-iminopyridyl Pd(II) catalysts. Additionally, Pd1 exhibited the best performance in propylene-MA copolymerization as it displayed the highest MA incorporation ratio of up to 36.5 mol%. All the three catalysts are capable of generating partially chain-straightened P-MA co-oligomers and the activities decrease gradually while the molecular weight increases with the increasing steric hindrance of the alkyl substituent (H < Me < n-Bu). Compared to Pd4 with the rigid 8-aryl substituent, the flexible 8-alkyl-iminopyridyl Pd(II) catalysts (Pd1-3) not only showed much higher activities in the propylene oligomerization, but also yielded P-MA co-oligomers with significantly higher incorporation ratios in the propylene co-oligomerization.
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Affiliation(s)
- Huayin Sun
- School of Chemical and Materials Engineering, Huainan Normal University, Huainan 232038, China
| | - Huijun Fan
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei 230601, China
| | - Chuangao Zhu
- School of Chemical and Materials Engineering, Huainan Normal University, Huainan 232038, China
| | - Wenping Zou
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, TX 78712, USA
| | - Shengyu Dai
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei 230601, China
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, Changzhou University, Changzhou 213164, China
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13
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Lu Z, Xu X, Luo Y, He S, Fan W, Dai S. Unexpected Effect of Catalyst’s Structural Symmetry on the Branching Microstructure of Polyethylene in Late Transition Metal Polymerization Catalysis. ACS Catal 2022. [DOI: 10.1021/acscatal.2c04525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Zhou Lu
- School of Chemical and Environmental Engineering, Anhui University, Wuhu, Anhui 241000, China
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui Polytechnic University, Hefei, Anhui 230601, China
| | - Xiaowei Xu
- PetroChina Petrochemical Research Institute, Beijing 102206, China
| | - Yi Luo
- PetroChina Petrochemical Research Institute, Beijing 102206, China
| | - Shengbao He
- PetroChina Petrochemical Research Institute, Beijing 102206, China
| | - Weigang Fan
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui Polytechnic University, Hefei, Anhui 230601, China
| | - Shengyu Dai
- School of Chemical and Environmental Engineering, Anhui University, Wuhu, Anhui 241000, China
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui Polytechnic University, Hefei, Anhui 230601, China
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14
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Controllable Preparation of Branched Polyolefins with Various Microstructural Units via Chain-walking Ethylene and Pentene Polymerizations. CHINESE JOURNAL OF POLYMER SCIENCE 2022. [DOI: 10.1007/s10118-022-2875-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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15
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Developments in late transition metal catalysts with high thermal stability for ethylene polymerization: A crucial aspect from laboratory to industrialization. Eur Polym J 2022. [DOI: 10.1016/j.eurpolymj.2022.111693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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16
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Liao YD, Cai Q, Dai SY. Synthesis of High Molecular Weight Polyethylene and E-MA Copolymers Using Iminopyridine Ni(II) and Pd(II) Complexes Containing a Flexible Backbone and Rigid Axial Substituents. CHINESE JOURNAL OF POLYMER SCIENCE 2022. [DOI: 10.1007/s10118-022-2847-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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17
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Ding B, Chang G, Yan Z, Dai S. Ethylene (co) oligomerization using iminopyridyl Ni(II) and Pd(II) complexes bearing benzocycloalkyl moieties to access hyperbranched ethylene oligomers and ethylene-MA co-oligomers. Front Chem 2022; 10:961426. [PMID: 35991594 PMCID: PMC9386154 DOI: 10.3389/fchem.2022.961426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Accepted: 06/27/2022] [Indexed: 11/13/2022] Open
Abstract
Hyperbranched ethylene oligomers and polar functionalized co-oligomers synthesized via ethylene chain walking (co) oligomerization is a very attractive strategy. In this study, a series of dibenzhydryl iminopyridyl ligands with benzocycloalkyl and naphthyl moieties and the corresponding Ni(II) and Pd(II) complexes were synthesized and characterized. The Ni(II) complexes were highly effective in ethylene oligomerization and ethylene oligomers with hyperbranched microstructures were generated from this system. The corresponding Pd(II) complexes showed moderate oligomerization activities in ethylene oligomerization and hyperbranched ethylene oligomers were also yielded from the system. More significantly, the Pd(II) complexes can also effectively promote the co-oligomerization of ethylene with methyl acrylate (MA) to obtain hyperbranched polar functionalized ethylene-MA co-oligomers. The reaction temperature, catalyst ligand structure and metal type all have significant effects on ethylene (co) oligomerization with respect to catalytic activity, molecular weight and topology of the oligomers.
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Affiliation(s)
- Beihang Ding
- Institute of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, China
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, China
| | - Guanru Chang
- School of Chemistry and Chemical Engineering, Key Laboratory of Inorganic Functional Material, Huangshan University, Huangshan, China
| | - Zhengpeng Yan
- Institute of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, China
| | - Shengyu Dai
- Institute of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, China
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, China
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18
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Ge Y, Lu Z, Dai S. Flexible Axial Shielding Strategy for the Synthesis of High-Molecular-Weight Polyethylene and Polar Functionalized Polyethylene with Pyridine-Imine Ni(II) and Pd(II) Complexes. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00207] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- You Ge
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China
| | - Zhou Lu
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui 230601, China
| | - Shengyu Dai
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui 230601, China
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19
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Guo L, Chen W, Wang W, An W, Gao S, Zhao Y, Luo M, He G, Liu T. Ortho-substituent Effect on Metal Coordination Geometry, Chain Microstructure and Polymer Properties in α-Diimine Nickel-catalyzed Long Chain α-Olefin Polymerization. J Catal 2022. [DOI: 10.1016/j.jcat.2022.05.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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20
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Ge Y, Cai Q, Wang Y, Gao J, Chi Y, Dai S. Synthesis of High-Molecular-Weight Branched Polyethylene Using a Hybrid "Sandwich" Pyridine-Imine Ni(II) Catalyst. Front Chem 2022; 10:886888. [PMID: 35601545 PMCID: PMC9114440 DOI: 10.3389/fchem.2022.886888] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 04/19/2022] [Indexed: 11/13/2022] Open
Abstract
Most pyridine-imine Ni(II) and Pd(II) catalysts tend to yield low-molecular-weight polyethylene and ethylene-based copolymers in olefin insertion polymerization, as the unilateral axial steric structure of such complexes often cannot provide effective shielding of the metal center. In this study, we synthesized a series of hybrid "semi-sandwich" and "sandwich" type pyridine-imine Ni(II) complexes by incorporating diarylmethyl or dibenzosuberyl groups onto 8-aryl-naphthyl motif. The as-prepared Ni(II) complexes afforded highly branched polyethylene with high molecular weights (level of 105 g/mol), and moderate activities (level of 105 g/(molh)) in ethylene polymerization. Most interestingly, compared to "semi-sandwich" Ni(II) complexes bearing (2-diarylmethyl-8-aryl)naphthyl units, the "full-sandwich" counterpart containing (2-dibenzosuberyl-8-aryl)naphthyl motif was able to produce higher-molecular-weight polyethylene with higher branching density. In addition, the effect of remote non-conjugated electronic substituents in diarylmethyl groups of the Ni(II) system was also observed in ethylene polymerization.
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Affiliation(s)
- You Ge
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, China
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, China
| | - Qi Cai
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, China
| | - Yuyin Wang
- Key Laboratory of Advanced Structural Materials of Ministry of Education, College of Material Science and Engineering, College of Chemistry and Life Science, Advanced Institute of Materials Science, Changchun University of Technology, Changchun, China
| | - Jiangang Gao
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, China
| | - Yue Chi
- Key Laboratory of Advanced Structural Materials of Ministry of Education, College of Material Science and Engineering, College of Chemistry and Life Science, Advanced Institute of Materials Science, Changchun University of Technology, Changchun, China
| | - Shengyu Dai
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, China
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, China
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21
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Lu W, Liao Y, Dai S. Facile Access to Ultra-Highly Branched Polyethylenes Using Hybrid “Sandwich” Ni(II) and Pd(II) Catalysts. J Catal 2022. [DOI: 10.1016/j.jcat.2022.05.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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22
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Lu W, Wang H, Fan W, Dai S. Exploring the Relationship between the Polyethylene Microstructure and Spatial Structure of α-Diimine Pd(II) Catalysts via a Hybrid Steric Strategy. Inorg Chem 2022; 61:6799-6806. [PMID: 35476412 DOI: 10.1021/acs.inorgchem.1c03969] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The branching density of polyethylene generated in the α-diimine Pd(II) system is usually very high, largely independent of simple ligand modifications with steric or electronic perturbations, or the polymerization conditions. In this study, we designed and synthesized a class of bulky hybrid α-diimine Pd(II) catalysts combining ortho-diarylmethyl and ortho-phenyl moieties to explore the relationship between the polyethylene microstructure and the spatial structure of catalysts. In ethylene polymerization, the hybrid α-diimine Pd(II) catalysts exhibited high activities (well above 105 g·mol-1·h-1) and yielded highly branched (90-110/1000C) polyethylenes with high molecular weights (up to 278.3 kg/mol). Compared with the two corresponding symmetrical ortho-diarylmethyl-based or ortho-phenyl-based Pd(II) catalysts, the hybrid catalysts generated polyethylene of significantly higher branching densities (92 vs 28-34/1000C) in marked higher activities. Similar phenomena are also observed in the copolymerization of ethylene with polar monomers. Moreover, the hybrid Pd(II) catalysts can more efficiently promote the copolymerization of ethylene with various polar monomers in comparison to the corresponding symmetrical catalysts. The more open spatial environment around the metal center by using a hybrid steric strategy was proposed to be responsible for above advantages.
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Affiliation(s)
- Weiqing Lu
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui 230601, China
| | - Hui Wang
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China
| | - Weigang Fan
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui 230601, China
| | - Shengyu Dai
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui 230601, China.,School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China
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23
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Wang X, Xu M, Zhang S, Qasim M, Chen M. Fluorine Effect on α-Imino-ketone- and Phenoxyiminato Nickel-Catalyzed Ethylene Homo- and Copolymerization. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Xiaoyue Wang
- Institutes of Physical Science and Information Technology, School of Computer Science and Technology, Anhui University, Hefei 230601, Anhui, China
| | - Mengli Xu
- Institutes of Physical Science and Information Technology, School of Computer Science and Technology, Anhui University, Hefei 230601, Anhui, China
| | - Shaojie Zhang
- Institutes of Physical Science and Information Technology, School of Computer Science and Technology, Anhui University, Hefei 230601, Anhui, China
| | - Muhammad Qasim
- Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Min Chen
- Institutes of Physical Science and Information Technology, School of Computer Science and Technology, Anhui University, Hefei 230601, Anhui, China
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24
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Soshnikov IE, Semikolenova NV, Bryliakov KP, Antonov AA, Talsi EP. Ni(I) Intermediates Formed upon Activation of a Ni(II) α-Diimine Ethylene Polymerization Precatalyst with AlR 3 (R = Me, Et, and iBu), AlR 2Cl (R = Me, Et), and MMAO: A Comparative Study. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00065] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Igor E. Soshnikov
- Boreskov Institute of Catalysis, Pr. Lavrentieva, 5, 630090, Novosibirsk, Russian Federation
| | - Nina V. Semikolenova
- Boreskov Institute of Catalysis, Pr. Lavrentieva, 5, 630090, Novosibirsk, Russian Federation
| | - Konstantin P. Bryliakov
- Boreskov Institute of Catalysis, Pr. Lavrentieva, 5, 630090, Novosibirsk, Russian Federation
| | - Artem A. Antonov
- Boreskov Institute of Catalysis, Pr. Lavrentieva, 5, 630090, Novosibirsk, Russian Federation
| | - Evgenii P. Talsi
- Boreskov Institute of Catalysis, Pr. Lavrentieva, 5, 630090, Novosibirsk, Russian Federation
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25
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Wang H, Duan G, Fan H, Dai S. Second coordination sphere effect of benzothiophene substituents on chain transfer and chain walking in ethylene insertion polymerization. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.124707] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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26
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Chu YK, Hu XQ, Zhang Y, Liu DJ, Zhang YX, Jian ZB. Influence of Backbone and Axial Substituent of Catalyst on α-Imino-ketone Nickel Mediated Ethylene (Co)Polymerization. CHINESE JOURNAL OF POLYMER SCIENCE 2022. [DOI: 10.1007/s10118-022-2691-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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27
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Xia J, Kou S, Zhang Y, Jian Z. Strategies cooperation on designing nickel catalysts to access ultrahigh molecular weight polyethylenes. POLYMER 2022. [DOI: 10.1016/j.polymer.2021.124478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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28
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Zhang Q, Liu M, Ma Y, Ye Z, Liang T, Sun W. Highly Active and Thermostable Camphyl α‐Diimine Nickel (II) Catalysts for Ethylene Polymerization: Effects of
N
‐Aryl Substituting Groups on Catalytic Properties and Branching Structures of Polyethylene. Appl Organomet Chem 2022. [DOI: 10.1002/aoc.6606] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Qiuyue Zhang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing China
- CAS Research/Education Center for Excellence in Molecular Sciences University of Chinese Academy of Sciences Beijing China
| | - Ming Liu
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing China
- CAS Research/Education Center for Excellence in Molecular Sciences University of Chinese Academy of Sciences Beijing China
| | - Yanping Ma
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing China
| | - Zhibin Ye
- Department of Chemical and Materials Engineering Concordia University Quebec Canada
| | - Tongling Liang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing China
| | - Wen‐Hua Sun
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing China
- CAS Research/Education Center for Excellence in Molecular Sciences University of Chinese Academy of Sciences Beijing China
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29
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Lu Z, Liao Y, Fan W, Dai S. Efficient suppression of the chain transfer reaction in ethylene coordination polymerization with dibenzosuberyl substituents. Polym Chem 2022. [DOI: 10.1039/d2py00282e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Catalysts with dibenzosuberyl substituents possess a superior ability to suppress chain transfer in ethylene (co)polymerization, producing high molecular weight polyethylenes and functionalized polyethylenes (ethylene-MA copolymers).
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Affiliation(s)
- Zhou Lu
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui, 230601, China
| | - Yudan Liao
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui, 230601, China
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China
| | - Weigang Fan
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui, 230601, China
| | - Shengyu Dai
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui, 230601, China
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China
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30
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Yan Z, Bi H, Ding B, Wang H, Xu G, Dai S. A rigid-flexible double-layer steric strategy for ethylene (co)oligomerization with pyridine-imine Ni( ii) and Pd( ii) complexes. NEW J CHEM 2022. [DOI: 10.1039/d2nj00183g] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A rigid-flexible double-layer steric strategy enhances the molecular weight of the resulting ethylene oligomers and promotes the co-oligomerization of ethylene and methyl acrylate.
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Affiliation(s)
- Zhengpeng Yan
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui, 230601, China
| | - Huiqin Bi
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China
| | - Beihang Ding
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui, 230601, China
| | - Hui Wang
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China
| | - Guoyong Xu
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui, 230601, China
| | - Shengyu Dai
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui, 230601, China
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China
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31
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Lu Z, Chang G, Wang H, Jing K, Dai S. A Dual Steric Enhancement Strategy in α-Diimine Nickel and Palladium Catalysts for Ethylene Polymerization and Copolymerization. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00568] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Zhou Lu
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui 230601, People’s Republic of China
| | - Guanru Chang
- School of Chemistry and Chemical Engineering, Key Laboratory of Inorganic Functional Material, Huangshan University, Huangshan, Anhui 245041, People’s Republic of China
| | - Hui Wang
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, People’s Republic of China
| | - Kun Jing
- Nanjing Research Institute of Yangzi Petrochemical Co., Ltd., SINOPEC, Nanjing, Jiangsu 210048, People’s Republic of China
| | - Shengyu Dai
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui 230601, People’s Republic of China
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, People’s Republic of China
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32
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Chen A, Liao D, Chen C. Promoting Ethylene (co)Polymerization in Aliphatic Hydrocarbon Solvents Using
tert
‐Butyl
Substituted Nickel Catalysts. CHINESE J CHEM 2021. [DOI: 10.1002/cjoc.202100642] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ao Chen
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China Hefei Anhui 230026 China
| | - Daohong Liao
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China Hefei Anhui 230026 China
| | - Changle Chen
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China Hefei Anhui 230026 China
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33
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Fan H, Chang G, Bi H, Gui X, Wang H, Xu G, Dai S. Facile Synthesis of Hyperbranched Ethylene Oligomers and Ethylene/Methyl Acrylate Co-oligomers with Different Microscopic Chain Architectures. ACS POLYMERS AU 2021; 2:88-96. [PMID: 36855342 PMCID: PMC9954315 DOI: 10.1021/acspolymersau.1c00039] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Low-molecular-weight (MW) ethylene oligomers with hyperbranched microstructures are often difficult to be synthesized by traditional catalytic processes. In this study, a series of N-terphenyl iminopyridyl ligands and the corresponding Pd(II) and Ni(II) complexes bearing remote conjugated substituents with different electronic effects (H, Me, F, Cl, and tBu) were synthesized in a simple and efficient way. These Pd(II) and Ni(II) complexes were highly effective in the ethylene oligomerization and co-oligomerization with methyl acrylate (MA). Low-MW ethylene oligomers with hyperbranched microstructures were generated using the iminopyridyl Pd(II) and Ni(II) complexes in ethylene oligomerization. More importantly, polar functionalized ethylene-MA co-oligomers with low MWs and varying incorporation ratios were generated via ethylene and MA co-oligomerization using the Pd(II) complexes. Most notably, these ethylene oligomers obtained by different metal species showed a significant difference in microscopic chain architectures. The remote conjugated electron effect showed little effect on the polymerization parameters of the iminopyridyl system, which is very different from those of the salicylaldiminato system.
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Affiliation(s)
- Huijun Fan
- Institutes
of Physical Science and Information Technology, Key Laboratory of
Structure and Functional Regulation of Hybrid Materials of Ministry
of Education, Anhui University, Hefei, Anhui 230601, China
| | - Guanru Chang
- School
of Chemistry and Chemical Engineering, Key Laboratory of Inorganic
Functional Material, Huangshan University, Huangshan, Anhui 245041, China
| | - Huiqin Bi
- School
of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China
| | - Xu Gui
- School
of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China
| | - Hui Wang
- School
of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China,
| | - Guoyong Xu
- Institutes
of Physical Science and Information Technology, Key Laboratory of
Structure and Functional Regulation of Hybrid Materials of Ministry
of Education, Anhui University, Hefei, Anhui 230601, China,
| | - Shengyu Dai
- Institutes
of Physical Science and Information Technology, Key Laboratory of
Structure and Functional Regulation of Hybrid Materials of Ministry
of Education, Anhui University, Hefei, Anhui 230601, China,School
of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China,
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34
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Abstract
Nickel(II) complexes with bidentate N,N-α-diimine ligands constitute a broad class of promising catalysts for the synthesis of branched polyethylenes via ethylene homopolymerization. Despite extensive studies devoted to the rational design of new Ni(II) α-diimines with desired catalytic properties, the polymerization mechanism has not been fully rationalized. In contrast to the well-characterized cationic Ni(II) active sites of ethylene polymerization and their precursors, the structure and role of Ni(I) species in the polymerization process continues to be a “black box”. This perspective discusses recent advances in the understanding of the nature and role of monovalent nickel complexes formed in Ni(II) α-diimine-based ethylene polymerization catalyst systems.
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35
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Liu Y, Harth E. Distorted Sandwich α‐Diimine Pd
II
Catalyst: Linear Polyethylene and Synthesis of Ethylene/Acrylate Elastomers. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202107039] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Yu‐Sheng Liu
- Center of Excellence in Polymer Chemistry Department of Chemistry University of Houston 3585 Cullen Blvd Houston TX 77204 USA
| | - Eva Harth
- Center of Excellence in Polymer Chemistry Department of Chemistry University of Houston 3585 Cullen Blvd Houston TX 77204 USA
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36
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Investigations of ligand backbone effects on bulky diarylmethyl-based nickel(II) and palladium(II) catalyzed ethylene polymerization and copolymerization. J Organomet Chem 2021. [DOI: 10.1016/j.jorganchem.2021.122046] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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37
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38
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Chen SY, Pan RC, Liu Y, Lu XB. Bulky o-Phenylene-Bridged Bimetallic α-Diimine Ni(II) and Pd(II) Catalysts in Ethylene (Co)polymerization. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00374] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Shi-Yu Chen
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, People’s Republic of China
| | - Ru-Chao Pan
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, People’s Republic of China
| | - Ye Liu
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, People’s Republic of China
| | - Xiao-Bing Lu
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, People’s Republic of China
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39
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Peng D, Chen C. Photoresponsive Palladium and Nickel Catalysts for Ethylene Polymerization and Copolymerization. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202107883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Dan Peng
- Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China Hefei China
| | - Changle Chen
- Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China Hefei China
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40
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Nazarov IV, Bermesheva EV, Potapov KV, Khesina ZB, Il'in MM, Melnikova EK, Bermeshev MV. Palladium complex with tetrahydronaphthyl-substituted diimine ligand as a catalyst for polymerization of norbornenes and diazoacetates. MENDELEEV COMMUNICATIONS 2021. [DOI: 10.1016/j.mencom.2021.09.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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41
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Ge Y, Li S, Wang H, Dai S. Synthesis of Branched Polyethylene and Ethylene-MA Copolymers Using Unsymmetrical Iminopyridyl Nickel and Palladium Complexes. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00388] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- You Ge
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui, 230601, China
| | - Shuaikang Li
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui, 230601, China
| | - Hui Wang
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui, 241000, China
| | - Shengyu Dai
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui, 230601, China
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui, 241000, China
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42
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Harth E, Liu YS. Distorted Sandwich a-Diimine Pd(II) Catalyst: Linear Polyethylene and Synthesis of Ethylene/Acrylate Elastomers. Angew Chem Int Ed Engl 2021; 60:24107-24115. [PMID: 34403566 DOI: 10.1002/anie.202107039] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 07/29/2021] [Indexed: 11/09/2022]
Abstract
The introduction of m-xylyl substituents to α-diimine Pd(II) catalyst promotes living ethylene polymerization at room temperature and low pressure to yield high molecular weight polyethylene (PE) with low branching (<17/1000C). m-Xylyl groups provide a highly effective blockage to the axial sites of the catalytic center and form a distorted sandwich geometry. The shielding prevents chain-transfer and easy accessibility of polar monomers, leading to a living polymerization. Conducting a light irradiation as part of the one-step metal-organic insertion light initiated radical (MILRad) process leads to diblock copolymers of ethylene and acrylates. Incorporation of different acrylate block sequences can significantly modify the mechanical and chemical properties of block copolymers which can be modulated to be a hard plastic, elastomer, or semi-amorphous polymer.
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Affiliation(s)
- Eva Harth
- University of Houston, Chemistry, 406 STL Building, United States, 77004, Houston, UNITED STATES
| | - Yu-Sheng Liu
- University of Houston System, Chemistry, UNITED STATES
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43
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Hu X, Zhang Y, Li B, Jian Z. Fluorinated α-Diimine Nickel Mediated Ethylene (Co)Polymerization. Chemistry 2021; 27:11935-11942. [PMID: 34114692 DOI: 10.1002/chem.202101521] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Indexed: 11/10/2022]
Abstract
Fluorine substituents in transition metal catalysts are of great importance in olefin polymerization catalysis; however, the comprehensive effect of fluorine substituents is elusive in seminal late transition metal α-diimine catalytic system. In this contribution, fluorine substituents at various positions (ortho-, meta-, and para-F) and with different numbers (Fn ; n=0, 1, 2, 3, 5) were installed into the well-defined N-terphenyl amine and thus were studied for the first time in the nickel α-diimine promoted ethylene polymerization and copolymerization with polar monomers. The position of the fluorine substituent was particularly crucial in these polymerization reactions in terms of catalytic activity, polymer molecular weight, branching density, and incorporation of polar monomer, and thus a picture on the fluorine effect was given. As a notable result, the ortho-F substituted α-diimine nickel catalyst produced highly linear polyethylenes with an extremely high molecular weight (Mw =8703 kDa) and a significantly low degree of branching of 1.4/1000 C; however, the meta-F and/or para-F substituted α-diimine nickel catalysts generated highly branched (up to 80.2/1000 C) polyethylenes with significantly low molecular weights (Mw =20-50 kDa).
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Affiliation(s)
- Xiaoqiang Hu
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Renmin Street 5625, Changchun, 130022, China.,University of Science and Technology of China, Hefei, 230026, China
| | - Yixin Zhang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Renmin Street 5625, Changchun, 130022, China
| | - Baixiang Li
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Renmin Street 5625, Changchun, 130022, China
| | - Zhongbao Jian
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Renmin Street 5625, Changchun, 130022, China.,University of Science and Technology of China, Hefei, 230026, China
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44
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Acenaphthene-Based N-Heterocyclic Carbene Metal Complexes: Synthesis and Application in Catalysis. Catalysts 2021. [DOI: 10.3390/catal11080972] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
N-Heterocyclic carbene (NHC) ligands have become a privileged structural motif in modern homogenous and heterogeneous catalysis. The last two decades have brought a plethora of structurally and electronically diversified carbene ligands, enabling the development of cutting-edge transformations, especially in the area of carbon-carbon bond formation. Although most of these were accomplished with common imidazolylidene and imidazolinylidene ligands, the most challenging ones were only accessible with the acenaphthylene-derived N-heterocyclic carbene ligands bearing a π-extended system. Their superior σ-donor capabilities with simultaneous ease of modification of the rigid backbone enhance the catalytic activity and stability of their transition metal complexes, which makes BIAN-NHC (BIAN—bis(imino)acenaphthene) ligands an attractive tool for the development of challenging reactions. The present review summarizes synthetic efforts towards BIAN-NHC metal complexes bearing acenaphthylene subunits and their applications in modern catalysis, with special emphasis put on recently developed enantioselective processes.
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45
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Liao D, Behzadi S, Hong C, Zou C, Qasim M, Chen M. Influence of thiopheneyl‐based twisted backbone on the properties of α‐diimine nickel catalysts in ethylene polymerization. Appl Organomet Chem 2021. [DOI: 10.1002/aoc.6406] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Daohong Liao
- Department of Polymer Science and Engineering University of Science and Technology of China Hefei China
| | - Shabnam Behzadi
- Department of Polymer Science and Engineering University of Science and Technology of China Hefei China
| | - Changwen Hong
- Department of Polymer Science and Engineering University of Science and Technology of China Hefei China
| | - Chen Zou
- Department of Polymer Science and Engineering University of Science and Technology of China Hefei China
| | - Muhammad Qasim
- Department of Polymer Science and Engineering University of Science and Technology of China Hefei China
| | - Min Chen
- Institutes of Physical Science and Information Technology Anhui University Hefei China
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46
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Hu X, Zhang Y, Li B, Jian Z. Horizontally and Vertically Concerted Steric Strategy in
α‐Diimine
Nickel Promoted Ethylene (Co)Polymerization
†. CHINESE J CHEM 2021. [DOI: 10.1002/cjoc.202100312] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Xiaoqiang Hu
- State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences, Renmin Street 5625, Changchun Jilin 130022 China
- University of Science and Technology of China Hefei Anhui 230026 China
| | - Yixin Zhang
- State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences, Renmin Street 5625, Changchun Jilin 130022 China
| | - Baixiang Li
- State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences, Renmin Street 5625, Changchun Jilin 130022 China
| | - Zhongbao Jian
- State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences, Renmin Street 5625, Changchun Jilin 130022 China
- University of Science and Technology of China Hefei Anhui 230026 China
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47
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Zhu N, Liang T, Huang Y, Pang W, Chen M, Tan C. Influences of Ligand Backbone Substituents on Phosphinecarbonylpalladium and -nickel Catalysts for Ethylene Polymerization and Copolymerization with Polar Monomers. Inorg Chem 2021; 60:13080-13090. [PMID: 34357773 DOI: 10.1021/acs.inorgchem.1c01490] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A series of phosphinecarbonylpalladium and -nickel catalysts bearing various substituents on the ligand backbone were prepared, characterized, and used in ethylene polymerization and copolymerization with polar monomers. The Pd and Ni catalysts can achieve high activities as well as high polymer molecular weights in both ethylene polymerization and copolymerization with polar monomers. The electron-donating group from the carbonyl side can effectively increase the polymer molecular weights. Utilization of a cyclic backbone structure can increase the catalytic activities at the expense of the polymer molecular weights. Moreover, installation of a pyridyl moiety in the ligand backbone can enable Lewis acid responsiveness and can enhance the polymerization activities. These results suggest the importance of the ligand backbone for the properties of catalysts in ethylene polymerization and copolymerization reactions.
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Affiliation(s)
- Ningning Zhu
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Tao Liang
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Yongshuang Huang
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Wenmin Pang
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Min Chen
- Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, China
| | - Chen Tan
- Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, China
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48
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Peng D, Chen C. Photoresponsive Palladium and Nickel Catalysts for Ethylene Polymerization and Copolymerization. Angew Chem Int Ed Engl 2021; 60:22195-22200. [PMID: 34312948 DOI: 10.1002/anie.202107883] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/20/2021] [Indexed: 11/11/2022]
Abstract
In this contribution, we install an azobenzene functionality in olefin polymerization catalysts and use light to modulate their properties via photoinduced trans-cis isomerization of the azobenzene moiety. The initially targeted azobenzene-functionalized α-diimine palladium and nickel catalysts are not photoresponsive. To address this issue, an imine-amine system bearing interrupted conjugation with the metal center, and a sandwich-type α-diimine system bearing an azobenzene unit at a position covalently far from the metal center were prepared and studied. We demonstrate that light can be used to tune their properties in ethylene polymerization and copolymerization with polar comonomers, enabling light-induced control of the polymerization processes, polymer microstructures and polymer properties. More interestingly, the light-mediated property changes were attributed to ligand electronic effects in one system and ligand steric effects in the other.
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Affiliation(s)
- Dan Peng
- University of Science and Technology of China, Department of Polymer Science and Engineering, CHINA
| | - Changle Chen
- University of Science and Technology of China, Department of Polymer Science & Engineering, Jinzhai Rd 96, 230026, Hefei, CHINA
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49
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50
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Ge Y, Li S, Fan W, Dai S. Flexible "Sandwich" (8-Alkylnaphthyl α-Diimine) Catalysts in Insertion Polymerization. Inorg Chem 2021; 60:5673-5681. [PMID: 33783209 DOI: 10.1021/acs.inorgchem.0c03715] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
8-Arylnaphthyl substituents are privileged motifs frequently integrated into late-transition-metal catalysts, endowing them with an ability to retard chain transfer in ethylene polymerization. In this contribution, we disclose a sort of novel α-diiminenickel and -palladium complexes containing flexible 8-alkylnaphthyl in lieu of rigid 8-arylnaphthyl and their catalytic performance in ethylene polymerization. An interesting feature of these 8-alkylnaphthyl-substituted α-(diimine)PdMeCl complexes is that they present as a mixture of syn and anti isomers (syn:anti = ca. 1:1 ratio, determined by 1H and 13C NMR spectroscopy). In ethylene polymerization, these nickel complexes displayed high activity (up to 3.37 × 106 g mol-1 h-1) and generated branched polyethylenes with broad or bimodal molecular weight distributions (4.6-29.3), while the corresponding palladium complexes exhibited moderate activity, producing highly branched polyethylenes with unimodal and narrow molecular weight distributions (<1.8). In ethylene (E)/methyl acrylate (MA) copolymerization, highly branched E-MA copolymers with considerable MA incorporations were achieved by these palladium complexes. Most interestingly, compared to rigid 8-arylnaphthyl-substituted α-diiminenickel and -palladium complexes, the flexible 8-alkylnaphthyl ones showed significantly improved activity and generated lower or comparable molecular weight polyethylenes or E-MA copolymers.
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Affiliation(s)
- You Ge
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui 230601, China
| | - Shuaikang Li
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui 230601, China
| | - Weigang Fan
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui 230601, China
| | - Shengyu Dai
- Institutes of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui 230601, China
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