Inhibitors vinyl acetate monomer process

Vinyl acetate is normally inhibited with hydroquinone to prevent polymerisation. A combination of too low a level of inhibitor and warm, moist storage conditions may lead to spontaneous polymerisation. This process involves autoxidation of acetaldehyde (a normal impurity produced by hy droly sis of the monomer) to a peroxide which initiates exothermic polymerisation as it decomposes. In bulk, this may accelerate to a dangerous extent. Other peroxides or radical sources will initiate the exothermic polymerisation. 

In summary, Table 3 presents a certain number of phenolic inhibitors that are used either during the process or storage of the main monomers including vinyl monomers such as acrylonitrile, vinyl acetate or acrolein. 

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