Trifluoromethoxy- and Fluorobenzhydryl-Tuned Nickel Catalysts for Polyethylene Elastomers

A series of <i>para</i>-trifluoromethoxy-substituted and fluorobenzhydryl-functionalized 1,2-bis(imine)acenaphthene ligands: 1-[2,6-{(4-F-C<sub>6</sub>H<sub>4</sub>)<sub>2</sub>CH}<sub>2</sub>-4-F<sub>3</sub>COC<sub>6</...

Full description

Saved in:
Bibliographic Details
Main Authors: Ming Liu, Min Sun, Yanping Ma, Yizhou Wang, Mingfeng Li, Wen-Hua Sun
Format: Article
Language:English
Published: MDPI AG 2025-06-01
Series:Molecules
Subjects:
Online Access:https://www.mdpi.com/1420-3049/30/13/2706
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849429241177833472
author Ming Liu
Min Sun
Yanping Ma
Yizhou Wang
Mingfeng Li
Wen-Hua Sun
author_facet Ming Liu
Min Sun
Yanping Ma
Yizhou Wang
Mingfeng Li
Wen-Hua Sun
author_sort Ming Liu
collection DOAJ
description A series of <i>para</i>-trifluoromethoxy-substituted and fluorobenzhydryl-functionalized 1,2-bis(imine)acenaphthene ligands: 1-[2,6-{(4-F-C<sub>6</sub>H<sub>4</sub>)<sub>2</sub>CH}<sub>2</sub>-4-F<sub>3</sub>COC<sub>6</sub>H<sub>2</sub>N]-2-(ArN)C<sub>2</sub>C<sub>10</sub>H<sub>6</sub> (Ar = 2,6-Me<sub>2</sub>C<sub>6</sub>H<sub>3</sub> <b>L1</b>, 2,6-Et<sub>2</sub>C<sub>6</sub>H<sub>3</sub> <b>L2</b>, 2,6-iPr<sub>2</sub>C<sub>6</sub>H<sub>3</sub> <b>L3</b>, 2,4,6-Me<sub>3</sub>C<sub>6</sub>H<sub>2</sub> <b>L4</b>, 2,6-Et<sub>2</sub>-4-MeC<sub>6</sub>H<sub>2</sub> <b>L5</b>), were synthesized and used to generate their corresponding nickel(II) bromide complexes (<b>Ni1</b>–<b>Ni5</b>). Elemental analysis, <sup>19</sup>F NMR, and FT-IR spectroscopy were employed to characterize these five nickel complexes. Single-crystal X-ray diffraction of <b>Ni2</b> and <b>Ni4</b> confirmed distorted tetrahedral geometries. Upon activation with either EtAlCl<sub>2</sub> (ethylaluminum dichloride) or EASC (ethyl aluminum sesquichloride), these complexes showed exceptional high activities (up to 22.0 × 10<sup>6</sup> g PE mol<sup>−1</sup> (Ni) h<sup>−1</sup>) and remarkable thermal stability (4.82 × 10<sup>6</sup> g PE mol<sup>−1</sup>(Ni) h<sup>−1</sup> at 80 °C) towards ethylene polymerization. The resulting polyethylenes are highly branched, with the type and extent of branches tunable by temperature, solvent, and co-catalyst choice. Moreover, these polymers demonstrated excellent tensile strength (<i>σ<sub>b</sub></i> up to 20.7 MPa) and elastic recovery (up to 58%), characteristic of thermoplastic elastomers (TPEs). These results highlight the dual role of trifluoromethoxy and fluorobenzhydryl groups in enhancing catalytic performance and polymer properties.
format Article
id doaj-art-d5e7ab7d5d7447e4a3cc5120084d759a
institution Kabale University
issn 1420-3049
language English
publishDate 2025-06-01
publisher MDPI AG
record_format Article
series Molecules
spelling doaj-art-d5e7ab7d5d7447e4a3cc5120084d759a2025-08-20T03:28:25ZengMDPI AGMolecules1420-30492025-06-013013270610.3390/molecules30132706Trifluoromethoxy- and Fluorobenzhydryl-Tuned Nickel Catalysts for Polyethylene ElastomersMing Liu0Min Sun1Yanping Ma2Yizhou Wang3Mingfeng Li4Wen-Hua Sun5State Key Laboratory of Petroleum Molecular & Process Engineering, SINOPEC Research Institute of Petroleum Processing Co., Ltd., Beijing 100083, ChinaState Key Laboratory of Petroleum Molecular & Process Engineering, SINOPEC Research Institute of Petroleum Processing Co., Ltd., Beijing 100083, ChinaKey Laboratory of Engineering Plastics, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, ChinaKey Laboratory of Engineering Plastics, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, ChinaState Key Laboratory of Petroleum Molecular & Process Engineering, SINOPEC Research Institute of Petroleum Processing Co., Ltd., Beijing 100083, ChinaKey Laboratory of Engineering Plastics, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, ChinaA series of <i>para</i>-trifluoromethoxy-substituted and fluorobenzhydryl-functionalized 1,2-bis(imine)acenaphthene ligands: 1-[2,6-{(4-F-C<sub>6</sub>H<sub>4</sub>)<sub>2</sub>CH}<sub>2</sub>-4-F<sub>3</sub>COC<sub>6</sub>H<sub>2</sub>N]-2-(ArN)C<sub>2</sub>C<sub>10</sub>H<sub>6</sub> (Ar = 2,6-Me<sub>2</sub>C<sub>6</sub>H<sub>3</sub> <b>L1</b>, 2,6-Et<sub>2</sub>C<sub>6</sub>H<sub>3</sub> <b>L2</b>, 2,6-iPr<sub>2</sub>C<sub>6</sub>H<sub>3</sub> <b>L3</b>, 2,4,6-Me<sub>3</sub>C<sub>6</sub>H<sub>2</sub> <b>L4</b>, 2,6-Et<sub>2</sub>-4-MeC<sub>6</sub>H<sub>2</sub> <b>L5</b>), were synthesized and used to generate their corresponding nickel(II) bromide complexes (<b>Ni1</b>–<b>Ni5</b>). Elemental analysis, <sup>19</sup>F NMR, and FT-IR spectroscopy were employed to characterize these five nickel complexes. Single-crystal X-ray diffraction of <b>Ni2</b> and <b>Ni4</b> confirmed distorted tetrahedral geometries. Upon activation with either EtAlCl<sub>2</sub> (ethylaluminum dichloride) or EASC (ethyl aluminum sesquichloride), these complexes showed exceptional high activities (up to 22.0 × 10<sup>6</sup> g PE mol<sup>−1</sup> (Ni) h<sup>−1</sup>) and remarkable thermal stability (4.82 × 10<sup>6</sup> g PE mol<sup>−1</sup>(Ni) h<sup>−1</sup> at 80 °C) towards ethylene polymerization. The resulting polyethylenes are highly branched, with the type and extent of branches tunable by temperature, solvent, and co-catalyst choice. Moreover, these polymers demonstrated excellent tensile strength (<i>σ<sub>b</sub></i> up to 20.7 MPa) and elastic recovery (up to 58%), characteristic of thermoplastic elastomers (TPEs). These results highlight the dual role of trifluoromethoxy and fluorobenzhydryl groups in enhancing catalytic performance and polymer properties.https://www.mdpi.com/1420-3049/30/13/2706nickel catalystsdual steric-electronic tuninghighly branched polyethyleneshigh-temperature polymerizationthermoplastic elastomers (TPEs)
spellingShingle Ming Liu
Min Sun
Yanping Ma
Yizhou Wang
Mingfeng Li
Wen-Hua Sun
Trifluoromethoxy- and Fluorobenzhydryl-Tuned Nickel Catalysts for Polyethylene Elastomers
Molecules
nickel catalysts
dual steric-electronic tuning
highly branched polyethylenes
high-temperature polymerization
thermoplastic elastomers (TPEs)
title Trifluoromethoxy- and Fluorobenzhydryl-Tuned Nickel Catalysts for Polyethylene Elastomers
title_full Trifluoromethoxy- and Fluorobenzhydryl-Tuned Nickel Catalysts for Polyethylene Elastomers
title_fullStr Trifluoromethoxy- and Fluorobenzhydryl-Tuned Nickel Catalysts for Polyethylene Elastomers
title_full_unstemmed Trifluoromethoxy- and Fluorobenzhydryl-Tuned Nickel Catalysts for Polyethylene Elastomers
title_short Trifluoromethoxy- and Fluorobenzhydryl-Tuned Nickel Catalysts for Polyethylene Elastomers
title_sort trifluoromethoxy and fluorobenzhydryl tuned nickel catalysts for polyethylene elastomers
topic nickel catalysts
dual steric-electronic tuning
highly branched polyethylenes
high-temperature polymerization
thermoplastic elastomers (TPEs)
url https://www.mdpi.com/1420-3049/30/13/2706
work_keys_str_mv AT mingliu trifluoromethoxyandfluorobenzhydryltunednickelcatalystsforpolyethyleneelastomers
AT minsun trifluoromethoxyandfluorobenzhydryltunednickelcatalystsforpolyethyleneelastomers
AT yanpingma trifluoromethoxyandfluorobenzhydryltunednickelcatalystsforpolyethyleneelastomers
AT yizhouwang trifluoromethoxyandfluorobenzhydryltunednickelcatalystsforpolyethyleneelastomers
AT mingfengli trifluoromethoxyandfluorobenzhydryltunednickelcatalystsforpolyethyleneelastomers
AT wenhuasun trifluoromethoxyandfluorobenzhydryltunednickelcatalystsforpolyethyleneelastomers