Process for preventing discoloration in hydrolyzed ethylene-vinyl acetate copolymers by exposure to radiation

A process for the hydrolysis of a solid interpolymer of an ethylenically unsaturated hydrocarbon and a vinyl ester of a 2 to 6 carbon atom aliphatic carboxylic acid to products having a low yellowness index involves contacting of the solid interpolymer with a substantially anhydrous hydrolyzing agent and subjecting at least one of said interpolymer and said hydrolyzing agent to radiation. (U.S.)