METHOD OF INHIBITING POLYMERIZATION OF VINYLCYCLIC AND ALKYLVINYLCYCLIC COMPOUNDS Russian patent published in 1999 - IPC

FIELD: chemical technology, more particularly recovery of vinylcyclic and alkylvinylcyclic compounds from mixtures and/or purification by rectification. SUBSTANCE: method in carried out by adding polymerization inhibitor based on 2,2′,6,6′ tetramethylpiperidyl-4-fulvene N-oxide dimer or its solution. Inhibitor is product prepared by oxidation of mixture comprising at least 2,2′,6,6′-tetramethyl-4- oxopiperidine and 2,2′,6,6′-tetramethylpiperidyl-4-fulvene dimer. Inhibitor has the following components (wt %): 2,2′,6,6′-tetramethyl-4-oxopiperidine-1-oxyl, 15-70; di((2,2′,6,6′)- tetramethyl-4-oxopiperidyl-4-fulvene-1-oxyl, 12-65; 2,2′,6,6′- tetramethyl-4-oxopiperidine, 2-8; di-((2,2′,6,6′-tetramethyl-4- oxopiperidyl-4-dulvene, 4-11); di-(2,2′,6,6′-tetramethyl- piperidyl-4-furene-1-hydroxy, 1-3; and oxygen and/or nitrogen-containing and/or hydrocarbons, 3.5-10. Inhibitor is used in concentrated form or as solution in organic solvent. Said inhibitor is used to inhibit polymerization of styrene and/or alkylvinyl-pyridines and/or mixtures thereof with other agents at temperatures of not higher than 140 C, preferably up to 120 C. EFFECT: greater economic efficiency due to smaller amounts of polymer and reduced power consumption. 3 cl, 4 ex, 1 tbl