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Zhang Z, Kang X, Jiang Y, Cai Z, Li S, Cui D. Access to Disentangled Ultrahigh Molecular Weight Polyethylene via a Binuclear Synergic Effect. Angew Chem Int Ed Engl 2023; 62:e202215582. [PMID: 36418237 DOI: 10.1002/anie.202215582] [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: 10/24/2022] [Revised: 11/21/2022] [Accepted: 11/23/2022] [Indexed: 11/25/2022]
Abstract
Disentangled ultrahigh molecular weight polyethylene (dis-UHMWPE) has excellent processability but can be achieved under extreme conditions. Herein, we report ethylene polymerization with the binuclear half-sandwich scandium complexes C1-Sc2 and C2-Sc2 to afford UHMWPE. C1-Sc2 bearing a short linker shows higher activity and gives higher molecular weight PEs than C2-Sc2 containing a flexible spacer and the mononuclear Sc1 . Strikingly, all UHMWPEs isolated from C1-Sc2 under broad temperature range (25-120 °C) and wide ethylene pressures (2-13 bar) feature very low degree of entanglement as proved by rheological test, DSC annealing study and SEM. These dis-UHMWPEs are facilely mediated solid-state-process at 130 °C and their tensile strength and modulus reach up to 149.2 MPa and 1.5 GPa, respectively. DFT simulations reveal that the formation of dis-UHMWPE is attributed to the binuclear synergic effect and the agostic interaction between the active center and the growing chain.
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Affiliation(s)
- Zhen Zhang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022, Changchun, China.,Department of Materials Science and Engineering, Jilin University, 130022, Changchun, China
| | - Xiaohui Kang
- College of Pharmacy, Dalian Medical University, 116044, Dalian, China
| | - Yang Jiang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022, Changchun, China.,School of Applied Chemistry and Engineering, University of Science and Technology of China, 230026, Hefei, China
| | - Zhongyi Cai
- Department of Materials Science and Engineering, Jilin University, 130022, Changchun, China
| | - Shihui Li
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022, Changchun, China.,School of Applied Chemistry and Engineering, University of Science and Technology of China, 230026, Hefei, China
| | - Dongmei Cui
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022, Changchun, China.,School of Applied Chemistry and Engineering, University of Science and Technology of China, 230026, Hefei, China
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Guo F, Tsoureas N, Huang G, Tong M, Mansikkamäki A, Layfield RA. Isolation of a Perfectly Linear Uranium(II) Metallocene. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201912663] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Fu‐Sheng Guo
- Department of ChemistryUniversity of Sussex Falmer, Brighton BN1 9QR UK
| | - Nikolaos Tsoureas
- Department of ChemistryUniversity of Sussex Falmer, Brighton BN1 9QR UK
| | - Guo‐Zhang Huang
- Key Laboratory of Bioinorganic and Synthetic Chemistry of the Ministry of EducationSchool of ChemistrySun Yat-Sen University Guangzhou 510275 P. R. China
| | - Ming‐Liang Tong
- Key Laboratory of Bioinorganic and Synthetic Chemistry of the Ministry of EducationSchool of ChemistrySun Yat-Sen University Guangzhou 510275 P. R. China
| | - Akseli Mansikkamäki
- Department of ChemistryNanoscience CenterUniversity of Jyväskylä P.O. Box 35 40014 Jyväskylä Finland
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Guo FS, Tsoureas N, Huang GZ, Tong ML, Mansikkamäki A, Layfield RA. Isolation of a Perfectly Linear Uranium(II) Metallocene. Angew Chem Int Ed Engl 2020; 59:2299-2303. [PMID: 31710765 DOI: 10.1002/anie.201912663] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 10/21/2019] [Indexed: 11/11/2022]
Abstract
Reduction of the uranium(III) metallocene [(η5 -C5 i Pr5 )2 UI] (1) with potassium graphite produces the "second-generation" uranocene [(η5 -C5 i Pr5 )2 U] (2), which contains uranium in the formal divalent oxidation state. The geometry of 2 is that of a perfectly linear bis(cyclopentadienyl) sandwich complex, with the ground-state valence electron configuration of uranium(II) revealed by electronic spectroscopy and density functional theory to be 5f3 6d1 . Appreciable covalent contributions to the metal-ligand bonds were determined from a computational study of 2, including participation from the uranium 5f and 6d orbitals. Whereas three unpaired electrons in 2 occupy orbitals with essentially pure 5f character, the fourth electron resides in an orbital defined by strong 7s-6d z 2 mixing.
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Affiliation(s)
- Fu-Sheng Guo
- Department of Chemistry, University of Sussex, Falmer, Brighton, BN1 9QR, UK
| | - Nikolaos Tsoureas
- Department of Chemistry, University of Sussex, Falmer, Brighton, BN1 9QR, UK
| | - Guo-Zhang Huang
- Key Laboratory of Bioinorganic and Synthetic Chemistry of the Ministry of Education, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, P. R. China
| | - Ming-Liang Tong
- Key Laboratory of Bioinorganic and Synthetic Chemistry of the Ministry of Education, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, P. R. China
| | - Akseli Mansikkamäki
- Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, 40014, Jyväskylä, Finland
| | - Richard A Layfield
- Department of Chemistry, University of Sussex, Falmer, Brighton, BN1 9QR, UK
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Chakraborty A, Day BM, Durrant JP, He M, Tang J, Layfield RA. Double Ligand Activation in Silyl-Substituted Rare-Earth Cyclobutadienyl Complexes. Organometallics 2019. [DOI: 10.1021/acs.organomet.9b00763] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Anindita Chakraborty
- Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QR, United Kingdom
| | - Benjamin M. Day
- Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QR, United Kingdom
| | - James P. Durrant
- Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QR, United Kingdom
- Department of Chemistry, School of Natural Sciences, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Mian He
- Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QR, United Kingdom
| | - Jinkui Tang
- State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P.R. China
| | - Richard A. Layfield
- Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QR, United Kingdom
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