Poly free sulfurized compositions of unsaturated fatty substances and / or multiply unsaturated esters of acids and, if appropriate, olefins, their preparation and use as lubricant additives means.

摘要

The invention relates to compositions polysulfurized of fatty acids or esters of unsaturated (poly) obtained by a process which comprises in particular: - a step 1 in which is reacted, an unsaturated fatty substance and / or an ester of unsaturated acids (poly) in the presence or absence of a monoolefin aliphatic with, at least one compound chosen from among the monochloride and sulphur dichloride, thus forming an addition product, or "adduct"; - a step 2 in which is reacted, the hydrogen sulphide and / or a mercaptan with an alkali metal hydroxide or ammonium hydroxide in an aliphatic monoalcohol substantially anhydrous; - a step 3 in which are placed in contact with the adduct and possibly one monohalogenated hydrocarbon compound, with, the alcoholic solution obtained at the end of step 2; - a step 4 in which the monoalcohol is removed by distillation under reduced pressure. / p & & p & these compositions are used as additives for lubricants, mineral or synthetic.