Acetaldehyde

CAS RN: 75-07-0

Polymerization

The substance may polymerize under the influence of acids, alkaline materials, such as sodium hydroxide, in the presence of trace metals (iron) with fire or explosion hazard. (From table)
Impure material will polymerize readily in presence of trace metals (iron) or acids... Acetaldenyde is polymerized violently by conc. sulfuric acid.
Hazardous polymerization may occur.
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