Removal of metallic catalyst residue from polyphenylene ethers
Abstract
Abstract METALLIC CATALYST RESIDUES ARE REMOVED FROM REACTION SOLUTIONS CONTANING POLYPHENYLENE ETHERS PRODUCED BY AN OXIDATIVE COUPLING OF A PHENOL IN THE PRESENCE OF AN OXYGEN-CONTANING GAS AND A METAL-AMINE COMPLEX CATALYST REMOVAL OF THE METAL COMPONENT IS EFFECTED BY CONTACTING THE SOLUTION WITH A COMPOUND CAPABLE OF SELECTIVELY COMPLEXING WITH THE METAL TO FORM A WATER SOLUBLE COMPOUND, REMOVABLE BY SUBSEQUENT LIQUID-LIQUID EXTRACTION WITH AN AQUEOUS MEDIUM. THE PROCESS IS LESS EXPENSIVE THAN PRIOR ART PROCEDURES PROVIDES SOLUTIONS WHICH ARE MORE EFFICIENTLY DECOLORIZED, AND REDUCES THE METALLIC RESIDUE CONTENT OF THE POLYPHENYLENE ETHER TO LEVELS LOWER THAN OTHER COMMERCIALLY ACCEPTABLE METHODS.
Inventors
- 👤 J Bennett
- 👤 G Cooper
Bibliographic Details
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