The mechanism of polymerization inhibitors?
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My workshop produces styrene, and we use inhibitors worth hundreds of thousands of yuan each month. Dear sea friends, what is the inhibition mechanism of polymerization inhibitors? Thank you!
Polymerization inhibitors react with chain radicals to form non-radical species or low-reactivity radicals that cannot initiate polymerization, thereby stopping the polymerization process. To prevent olefin monomers from polymerizing during storage, transportation, etc., a small amount of polymerization inhibitor is often added to the monomers, and it is removed before use. Generally, the polymerization inhibitor is a solid substance with low volatility, and it can be removed during the distillation of the monomer. Hydroquinone, a commonly used polymerization inhibitor, can react with sodium hydroxide to form water-soluble sodium salts; therefore, it can be removed by washing with a 5%–10% sodium hydroxide solution. Inorganic polymerization inhibitors such as cuprous chloride and ferric trichloride can also be removed by acid washing.
When choosing a polymerization inhibitor, it is crucial to understand the principle behind polymer formation, and then select an appropriate chain terminator.
Reply to 2# woliaibo Thank you! “The commonly used polymerization inhibitor hydroquinone can react with sodium hydroxide to form water-soluble sodium salts, so it can be removed by washing with a 5%–10% sodium hydroxide solution. If sodium hydroxide solution is used to wash styrene, isn’t that introducing sodium hydroxide into the product again? It would be better to use water for washing.
Reply to 4# suncheng: Alkaline washing is also performed first, which helps to remove trace acidic substances from the manufacturing process and neutralize them; finally, water washing is used to remove the alkalis.
What are the problems with using it without treatment?
Hello, may I ask which company uses polymerization inhibitors?