Process for the chloromethylation of polymers for the production of anionic exchange resins
AssigneeDiamond Shamrock Corporation
InventorsJacques L. Boutier, Paul D. A. Grammont, Jean E. E. Herbin
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Abstract
Improved process for the chloromethylation of cross-linked vinylaromatic polymers and copolymers wherein a chlorine generator is incorporated into the reactants and a metallic chloride replaces part or all of the sulfuric acid used in forming the chloromethylating complex. The chloromethylated polymer may be further functionalized to produce an ion-exchange resin.
Claims7
In a process for the chloromethylation of cross-linked vinylaromatic polymers and copolymers using a chloromethylating complex based on chloromethyl methyl ether and sulfuric acid, the improvement which comprises incorporating chlorosulfonic acid into the reactants and replacing the sulfuric acid used in formation of the complex with an equivalent quantity of alkali metal or alkaline earth metal chloride, the amount of metal chloride being adjusted to provide a sulfuric acid/chloromethyl methyl ether molar ratio of at least 0.4 in the complex.
Dependencies are inferred from the claim text.