Nickel Phosphine Complexes: Synthesis, Characterization, and Behavior in the Polymerization of 1,3-Butadiene

Area of Science:

• Organometallic Chemistry
• Polymer Science
• Catalysis

Background:

• Nickel dichloride phosphine complexes are potential catalysts for olefin polymerization.
• Methylaluminoxane (MAO) is a common co-catalyst in olefin polymerization.

Purpose of the Study:

• To synthesize and characterize nickel dichloride phosphine complexes.
• To investigate the catalytic behavior of these complexes with MAO in butadiene polymerization.
• To compare the catalytic performance with analogous cobalt complexes.

Main Methods:

• Synthesis and X-ray crystallography of nickel complexes.
• Butadiene polymerization experiments using nickel complexes and MAO.
• Analysis of polymer microstructure (cis content).

Main Results:

• High-cis polybutadiene was consistently produced.
• Catalyst performance was independent of phosphine ligand and MAO/Ni ratio.
• Observed behavior differs significantly from analogous cobalt systems.

Conclusions:

• Nickel phosphine complexes offer robust catalytic systems for high-cis polybutadiene synthesis.
• The catalytic behavior of nickel differs from cobalt in butadiene polymerization.
• Ligand and co-catalyst ratio effects are less pronounced in nickel systems.