Isolation and Identification of the Major Extractable Impurity from Dowex 1×2 Resin

Structurally related low-molecular weight organic molecules which accounted for ∼0.13% of the total mass were isolated from commercial grade Dowex 1×2 resin. The structure of the main impurity is 2-chloromethyl-3-methoxyl-1-phenyl-1-propanol. This major component and the other extractables were the reaction products of monomeric styrene and chloromethyl methyl ether used in the production of Dowex 1×2 resin. These impurities were most likely entrapped in the polymer matrix and not sufficiently removed during the washing and cleaning process steps.