Aqueous Coordination-Insertion Copolymerization for Producing High Molecular Weight Polar Polyolefins

Area of Science:

• Polymer Chemistry
• Catalysis
• Green Chemistry

Background:

• Hydrocarbons are common reaction media for olefin polymerization.
• Water is an attractive but challenging medium for polar monomer copolymerization due to catalyst deactivation and low molecular weights.
• Developing catalysts for aqueous olefin polymerization is a significant goal in green chemistry.

Purpose of the Study:

• To develop novel catalysts enabling aqueous copolymerization of ethylene and polar monomers.
• To achieve high-molecular-weight linear polar polyolefins in water.
• To demonstrate improved performance in water compared to hydrocarbon solvents.

Main Methods:

• Development of neutral phosphinophenolato nickel catalysts.
• Aqueous coordination-insertion copolymerization of ethylene with various polar monomers.
• Characterization of resulting polyolefins for molecular weight and properties.

Main Results:

• Successfully synthesized high-molecular-weight linear polar polyolefins (219-549 kDa, 0.13-1.29 mol%) in water.
• Achieved better copolymerization results in water than in hydrocarbon solvents like toluene.
• The produced copolymers exhibit enhanced surface properties while retaining high-density polyethylene (HDPE) characteristics.

Conclusions:

• Neutral phosphinophenolato nickel catalysts enable unprecedented aqueous copolymerization of ethylene and polar monomers.
• This method provides a greener alternative to traditional hydrocarbon-based polymerization processes.
• The resulting polar polyolefins offer a unique combination of improved surface properties and desirable intrinsic characteristics.