Abstract: Describes compositions of 1,2-dichloroethylene, particularly trans-1,2-dichloroethylene, stabilized with effective stabilizing amounts of a combination of (a) C3 to C12 alkylene oxide, e.g., butylene oxide, (b) alcohol chosen from aliphatic and cycloaliphatic alcohols having from 2 to 8 carbon atoms, e.g., isopropanol, and (c) a material chosen from (i) C1 to C5 alkoxyphenol, e.g., 4-methoxyphenol, (ii) free radical stabilizer having at least one 2,2,6,6-tetra(lower alkyl)-1-piperidinyloxy-yl group, and (iii) mixtures of (i) and (ii). Also describes use of such compositions for vapor degreasing of soiled articles, e.g., metal parts and soldered circuit boards.

Abstract: Polychloroethylene, e.g., trichloroethylene and perchloroethylene, is stabilized with a stabilizing amount of a stable free radical stabilizer, e.g., a material having the 2,2,6,6-tetra(lower alkyl)-1-piperidinyloxy-yl free radical group, such as 2,2,6,6-tetramethyl-4-hydroxy-1-piperidinyloxy.