Catalysts for catalytic chain transfer
Cobaloxime derivatives and methods of producing cobaloxime derivatives are disclosed herein. Methods of producing decolorized homo- and co-polymers through polymerization of monomers in presence of the cobaloxime derivatives and decolorization of the produced polymer by exposing the polymer to a sorbent and, optionally, a solvent are also disclosed herein.
1. A cobaloxime derivative having the formula:
wherein Py is 4-(dimethylamino)pyridine, or
wherein R 7 is 4-(dimethylamino)pyridine, or
2. A method of producing decolorized homo- and co-polymers comprising:
(a) polymerizing at least one monomer in the presence of a cobaloxime derivative; and
(b) decolorizing the polymer produced by step (a) by exposing the polymer to a sorbent and, optionally, a solvent;
wherein the cobaloxime derivative has the formula
wherein Py is 4-(dimethylamino)pyridine, or
wherein R 7 is 4-(dimethylamino)pyridine, or
3. The method of claim 2 , wherein the at least one monomer is a methacrylate monomer, an acrylate monomer, a styrene monomer, a substituted styrene monomer, a maleate monomer, an itaconate monomer, an alpha-methylbutylroacetone monomer, or a chloropene monomer.
4. The method of claim 3 , wherein the methacrylate monomer is butyl methacrylate, 2-hydroxyethyl methacrylate, or glycidylmethacrylate.
5. The method of claim 2 , wherein the sorbent is basic alumina, a basic exchange resin, an acidic exchange resin, or activated carbon.
6. The method of claim 2 , wherein the solvent is methyl ethyl ketone, isopropanol, methanol, ethylacetate, butylacetate, toluene, xylene, or acetone.
7. The method of claim 2 , wherein the decolorized polymer of step (b) has an APHA of less than about 400.