摘要:
1,2-Bis-adducts of stable hindered nitroxide compounds with substituted ethylenes of formulas (I) & (II) are prepared by reacting two equivalents of nitroxyl compound with an ethylenically unsaturated compound such as styrene or an acrylate ester. These adducts are very effective inhibitors to prevent the premature polymerization of ethylenically unsaturated monomers when such monomers are distilled, processed or stored.
摘要:
When a nitroxyl compound is heated in an oxygen-free atmosphere with a vinyl aromatic monomer at 50-140°C for up to 60 days, it forms an activated inhibitor mixture which is superior to the nitroxyl compound itself in preventing the premature polymerization of a vinyl aromatic monomer during its processing and purification.