Dithiophosphoric acid polysulfide mixtures, useful as sulfur source in the vulcanization of rubber, are prepared by heating the corresponding disulfide with sulfur in the presence of a solvent

摘要

Stable dithiophosphoric acid polysulfide mixtures of formula (I) are prepared by heating the corresponding disulfide compounds (II) with sulfur optionally in the presence of a solvent. Process for preparing dithiophosphoric acid polysulfide mixtures of formula (I): R<1> - R<4> (same or different) = straight or branched 1-18 C alkyl, 1-18 C alkenyl, 5-28 C cycloalkyl, 5-28 C cycloalkenyl, 6-28 C aryl or 7-28 aralkyl n = 2.5-3.5 are prepared by heating the dithiophosphoric acid disulfide compound (II): in which R<1>-R<4> are as above, with 0.5-1.5 mol sulfur at temperatures of 100-140 deg C, optionally in the presence of a solvent.