PURPOSE: To prepare a high purity methylene chloride suitable as a polymerization solvent which does not corrode metals nor inhibit the polymerization, by adding a phenolic antioxidant and/or a conjugated diolefin as stabilizers to methylene chloride, thereby suppressing the formation of acids, chlorides, etc.
CONSTITUTION: A high purity methylene chloride is prepared by stabilizing methylene chloride with 0.1W80ppm, pref. 1W50ppm of a phenolic antioxidant (a polymer additive such as 2,6-di-t-butyl-4-methylphenol, p-t-butylcatechol, etc.) and/or ≤3%, pref. 50W10,000ppm of a conjugated diolefin (e.g. 1,3-butadiene, isoprene, etc.). The phenolic antioxidant is effective to inhibit the formation of acids, chlorides and aldehydes, and the conjugated diolefin inhibits the formation of acids and chlorides. The addition of the conjugated diolefin reduces the necessary amount of the phenolic antioxidant.
MIYAJI TAKUMI
TORIGOE KIICHI
