Polystyrene sulfonate aqueous solution with excellent storage stability and its manufacturing method

摘要

PROBLEM TO BE SOLVED: To provide a polystyrene sulfonate aqueous solution which improves the hue immediately after production to 60 or less and has excellent storage stability even for a long period of 60 days or more, and a method for producing the same. SOLUTION: A parastyrene sulfonate monomer is heated in an aqueous solvent using a water-soluble azo initiator as a polymerization initiator to carry out a polymerization reaction, and when the polymerization conversion rate becomes 80 to 100%, polystyrene sulfone is used. The APHA value of the obtained polystyrene sulfonate aqueous solution obtained by adding an amount of base having a pH of 11.0 to 13.0 and further heating and polymerizing the aqueous solution is 10 to 60 and the pH. Is 11.0 to 13.0, and when stored at 70 ° C., an aqueous polystyrene sulfonate solution, which maintains an APHA value of 10 to 60 and a pH of 11.0 to 13.0 for at least 60 days. And its manufacturing method. [Selection diagram] None