GB673611A - Stabilization of nuclear chlorostyrenes by 2,6-dinitrophenols - Google Patents

Abstract

A process for the stabilization against polymerization of nuclear chlorostyrenes containing not more than two chlorine atoms per molecule comprises dissolving in the chlorostyrene an inhibitor consisting of a 2,6-dinitrophenol <FORM:0673611/IV (b)/1> where R is hydrogen or an alkyl or cycloalkyl group containing not more than 6 carbon atoms. The chlorostyrenes may be pure individual compounds or mixtures, e.g. such as are produced by pyrolysis of mono-ethylated mono-and di-chlorobenzenes, by the dehydration of nuclearly chlorinated phenyl ethyl alcohols, and by the dechlorination of nuclearly chlorinated chlorethyl benzenes. Radicals represented by R mentioned are methyl, ethyl, propyl, butyl and cyclohexyl. Amounts of the inhibitor between 0.05 and 5 per cent by weight on the weight of chlorostyrene are mentioned. Examples show compositions of (1) mixed 2-, 3-, and 4-chlorostyrenes with 1 per cent of 2,6-dinitrophenol; (2) mixed 2-and 4-chlorostyrenes with 1 per cent of various 2,6-dinitrophenols; (3) pure 4-chlorostyrene and 2,6-dinitrophenol; (4) 2,5-dichlorostyrene and 2,6-dinitrophenol. The viscosity of the mixtures before and after heating to 100 DEG or 130 DEG C. is shown, and for comparison the results using other inhibitors under the same conditions is given.