114617-74-2Relevant articles and documents
Rigidifying Cation-Tunable Nickel Catalysts Increases Activity and Polar Monomer Incorporation in Ethylene and Methyl Acrylate Copolymerization
Tahmouresilerd, Babak,Xiao, Dawei,Do, Loi H.
, p. 19035 - 19043 (2021/12/13)
In this study, we synthesized and characterized two nickel complexes featuring conformationally rigid bisphosphine mono-oxide ligands, where one has an o-methoxyphenyl (Ni2) and the other has an o-(2-methoxyethoxy)phenyl (Ni3) substituent on the Pa? O moiety. We performed metal binding studies using Ni3 and found that its reaction with Li+ and Na+ most likely produced 1:1 and 1:1/2:1 nickel:alkali species in solution, respectively. The nickel complexes were competent catalysts for ethylene homopolymerization and copolymerization, with activities up to 3.8 × 103 and 8.1 × 10 kg mol-1 h-1, respectively. In reactions of ethylene with methyl acrylate (1.0 M), the addition of Li+ to Ni3 led to a 5.4-fold enhancement in catalyst activity and a 1.9-fold increase in polar monomer incorporation in comparison to those by Ni3 alone under optimized conditions. A comparison with other nickel catalysts reported for ethylene and methyl acrylate copolymerization revealed that our nickel-alkali catalysts are competitive with some of the most efficient Ni-based systems developed thus far.