Low molecular weight polymers and copolymers
AssigneeThe Glidden Company
InventorsJu-Chui Lin, Kirk J. Abbey
Life of this patent
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Abstract
New Cobalt(II) nitrilomethylidyne dipyrrole complexes such as Cobalt(II) 2,2'-[trimethylenebis(nitrilomethylidyne)]-dipyrrole, Cobalt(II) 2,2'-[o-phenylenebis(nitrilomethylidyne)]-dipyrrole and their basic ligand complexes are effective catalysts for molecular weight control in acrylate/methacrylate polymerization. The process comprises polymerizing monomers, especially including methacrylic monomer or methacrylic/acrylic monomer, in the presence of azo initiator and between 0.0001% and 0.01% of Cobalt(II) 2,2'-[trimethylenebis(nitrilomethylidyne)]-dipyrrole and/or Cobalt(II) 2,2'-[o-phenylenebis(nitrilomethylidyne)]-dipyrrole complexes to produce low molecular weight acrylate polymers and copolymers.
Claims11
A process for producing a low molecular weight polymer comprising copolymerizing ethylenically unsaturated monomers comprising a methacrylic monomer or a mixture of methacrylic and acrylic monomers, polymerized alone or with other ethylenic monomer in the presence of an effective amount of free-radical initiator in combination with 0.1 ppm to 5,000 ppm, basis monomer weight, Cobalt(II) nitrilomethylidyne dipyrrole complex catalyst comprising a Cobalt(II) nitrilomethylidyne dipyrrole complex modified by a basic ligand selected from the group consisting of amines, trisubstituted phosphines, and imidazole to produce a low molecule weight methacrylic polymer having a weight average molecular weight between 200 and 30,000.
Dependencies are inferred from the claim text.