University of Leicester
Browse
170711 Revised manuscript-GAS.pdf (1.55 MB)

Molecular weight control of polyethylene waxes using a constrained imino-cyclopenta[b]pyridyl-nickel catalyst

Download (1.55 MB)
journal contribution
posted on 2017-09-12, 11:36 authored by Zheng Wang, Youfu Zhang, Yanping Ma, Xinquan Hu, Gregory A. Solan, Yang Sun, Wen-Hua Sun
Five examples of nickel(II) bromide complexes bearing N,N-imino-cyclopenta[b]pyridines, [7-(ArN)-6,6-Me 2 C 8 H 5 N]NiBr 2 (Ar=2,6-Me 2 C 6 H 3 (Ni1), 2,6-Et 2 C 6 H 3 (Ni2), 2,6-i-Pr 2 C 6 H 3 (Ni3), 2,4,6-Me 3 C 6 H 2 (Ni4), 2,6-Et 2 -4-MeC 6 H 2 (Ni5)), have been prepared by the reaction of the corresponding ligand, L1-L5, with NiBr 2 (DME) (DME=1,2-dimethoxyethane). On crystallization from bench dichloromethane, Ni1 underwent adventitious reaction with water to give the aqua salt, [L1NiBr(OH 2 ) 3 ][Br] (Ni1'). The molecular structures of Ni1' and Ni3 have been structurally characterized, the latter revealing a bromide-bridged dimer. On activation with either MMAO or Et 2 AlCl, Ni1, Ni2, Ni4, and Ni5, all exhibited high activities for ethylene polymerization (up to 3.88 × 10 6 g(PE) mol -1 (Ni) h -1 ); the most sterically bulky Ni3 gave only low activity. Polyethylene waxes are a feature of the materials obtained which typically display low molecular weights (M w s), narrow M w distributions and unsaturated vinyl and vinylene functionalities. Notably, the catalyst comprising Ni1/Et 2 AlCl produced polyethylene with the lowest M w , 0.67 kg mol -1 , which is less than any previously reported data for any class of cycloalkyl-fused pyridine-nickel catalyst.

History

Citation

Journal of Polymer Science Part A: Polymer Chemistry, 2017, 55 (20), pp. 3494-3505

Author affiliation

/Organisation/COLLEGE OF SCIENCE AND ENGINEERING/Department of Chemistry

Version

  • AM (Accepted Manuscript)

Published in

Journal of Polymer Science Part A: Polymer Chemistry

Publisher

Wiley

issn

0887-624X

eissn

1099-0518

Acceptance date

2017-07-11

Copyright date

2017

Available date

2018-08-01

Publisher version

http://onlinelibrary.wiley.com/doi/10.1002/pola.28732/abstract

Notes

The file associated with this record is under embargo until 12 months after publication, in accordance with the publisher's self-archiving policy. The full text may be available through the publisher links provided above.

Language

en

Usage metrics

    University of Leicester Publications

    Categories

    No categories selected

    Keywords

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC