Recoverable polymer-bound homogeneous catalysts for catalytic chain transfer process
AssigneeE. I. Du Pont de Nemours and Company
InventorsHenry Edward Brynzda, Michael Charles Grady, Sigridur Soley Kristjansdottir, Christina M. Older, Matthew Arthur Page, Joachim C. Ritter, Wilson Tam
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Abstract
Disclosed herein are novel polymer-tethered ligands, metal complexes comprising these ligands, and the use of these complexes as chain transfer catalysts to control the molecular weight of oligomeric and polymeric materials produced in a radical polymerization process. The materials made by the processes disclosed herein have significantly reduced color, making them suitable for a wide range of color-critical end-uses, including automotive coatings.
Claims34
A process for the polymerization and co-polymerization of olefinic monomers employing a polymer-bound chain transfer catalyst to produce a molecular weight-controlled macronomer, said process comprising:
- (i) forming a polymerization medium comprising said olefinic monomers and said chain transfer catalyst, and optionally solvent(s), and
- (ii) polymerizing said olefinic monomers;
- (iii) effecting a phase partition of the chain transfer catalyst;
- and
- (iv) separating said chain transfer catalyst from said macromonomer, wherein said chain transfer catalyst is represented by a central moiety CAT and one or more substituents Poly positioned on CAT to form
- CAT−(Poly)x
- wherein said Poly radicals are linear or branched polymers with an average chain length equal to or greater than 20 atoms;
- wherein x is an integer greater than or equal to 1;
- wherein CAT comprises a metal atom coordinated to one or more ligands;
- and wherein said moiety CAT is defined such that the compound CAT-(R1)x is a chain transfer catalyst, wherein R1 is independently H or CH3;
- and wherein said Poly radicals are covalently bonded to one or more of said ligands.
A chain transfer catalyst composition represented by central moiety CAT and one or more substituents Poly positioned on CAT to form
- CAT-(Poly)x
- wherein said Poly radicals are linear or branched polymers with an average chain length equal to or greater than 20 atoms;
- wherein x is an integer greater than or equal to 1;
- wherein CAT comprises a metal atom coordinated to one or more liqands;
- and
- wherein said moiety CAT is defined such that the compound CAT-(R1)x is a chain transfer catalyst,
- wherein R1 is independently H or CH3;
- and
- wherein said Poly radicals are covalently bonded to one or more of said liqands.
Dependencies are inferred from the claim text.