To provide a method for manufacturing an ethylene/vinyl acetate resin emulsion excellent in controllability of emulsion polymerization, having an extremely low formaldehyde content, and excellent in creep resistance.
This method for manufacturing the ethylene/vinyl acetate resin emulsion comprises emulsion-polymerizing ethylene and vinyl acetate under pressure using a vinyl alcohol-based polymer having a saponification degree of at least 70 mole % as a dispersant and a redox polymerization initiator comprising hydrogen peroxide and tartaric acid and/or a metallic salt thereof, where (1) the pH of the polymerization system is adjusted to 3-7, (2) an iron compound is further added to the system, (3) the whole quantity of vinyl acetate is charged in the initial stage, (4) hydrogen peroxide is used in a total amount of 0.01-0.2 pt.wt. based on 100 pts.wt. of the total amount of the monomers, and (5) after the concentration of the unreacted vinyl acetate reduces to 10%, 20-40% of the total hydrogen peroxide is added to effect ageing.
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