GB680428A - Improvements in or relating to mineral oil compositions - Google Patents

Abstract

Sulphurized or phospho-sulphurized glycol diesters containing 5.8-11.4 per cent of sulphur are employed as additives in lubricating compositions (see Group III). The glycol diesters which are sulphurized or phospho-sulphurized, have the general formula <FORM:0680428/IV (b)/1> where R and R11 are unsaturated aliphatic hydrocarbon groups of at least 10 carbon atoms and R1 is a divalent aliphatic group consisting of a plurality of methylene groups in a chain, which chain may be interrupted by one or more oxygen or sulphur atoms. Glycol diesters of the above formula may be prepared by esterifying ethylene glycol, di- or tri-ethylene glycol or bis-(b -hydroxyethyl) sulphide with unsaturated fatty acids such as oleic acid, elaidic acid, erucic acid, linoleic acid or ricinoleic acid. The esters may be sulphurized by heating with sulphur or a mixture of sulphur and sulphur halide, and small amounts of acidic materials such as toluene sulphonic acid, sulphuric acid or phosphoric acid may be added to catalyse the sulphurization. The sulphurized esters may be phosphorized by heating with a phosphorus compound such as phosphorus pentasulphide, phosphorus sesquisulphide, phosphorus trichloride, phosphorus oxychloride or phosphorus pentoxide or with elemental phosphorus. The sulphurization and phosphorization may be carried out in an inert atmosphere, for example of nitrogen or of hydrogen sulphide. In the examples, glycol dioleate is sulphurized by heating with sulphur or with a mixture of sulphur and p S2Cl2; if desired, the glycol dioleate employed may contain some free oleic acid. The sulphurized glycol dioleate may be phosphorized by heating with P4S3. In further examples, diethylene glycol dioleate or dithiodiglycol dioleate are phosphosulphurized by heating first with sulphur and then with P4S3. Specification 471,593 is referred to. Oleyl phosphates.-An additional ingredient of the lubricating compositions (see Group III) may be a mixture of mono- and di-oleyl phosphates prepared by heating 1 mol. of P2O5 with 3 mols. of oleyl alcohol.ALSO:A composition especially suitable as a lubricant under extreme pressure conditions, for example a gear lubricant, comprises a major proportion of mineral oil and at least 0.1 per cent by weight based on the oil of a sulphurized or phospho-sulphurized glycol diester containing 5.8-11.4 per cent of sulphur, the glycol diester which is sulphurized or phospho-sulphurized being of the general formula <FORM:0680428/III/1> where R and R11 are unsaturated aliphatic hydrocarbon groups of at least 10 carbon atoms and R1 is a divalent aliphatic group consisting of a plurality of methylene groups in a chain, which chain may be interrupted by one or more sulphur or oxygen atoms. The composition may alternatively be a crankcase lubricant, a spindle oil, a turbine oil, an insulating oil, a transformer oil, a slushing composition or a grease. Glycol diesters of the above formula may be prepared by esterifying ethylene glycol, di- or tri-ethylene glycol or bis (b -hydroxyethyl) sulphide with unsaturated fatty acids such as oleic acid, elaidic acid, erucic acid, linoleic acid or ricinoleic acid. The esters may be sulphurized by heating with sulphur or a mixture of sulphur and a sulphur halide, and the sulphurized esters may thereupon be phosphorized by heating with a phosphorus sulphide such as phosphorus pentasulphide or sesquisulphide. The phosphorization may, however, be effected with other phosphorus compounds such as phosphorus trichloride, phosphorus oxychloride p or phosphorus pentoxide, or with elemental phosphorus. The lubricating composition may, if desired, contain a separate oil-soluble phosphorus-bearing component such as an alkyl acid phosphate. Suitable phosphorus-bearing substances are mono-oleyl phosphate, dioleyl phosphate, monolauryl phosphate, dilauryl phosphate, monocresyl phosphate, dicresyl phosphate, dicetyl phosphate and dioctyl phosphate. The presence in the composition of a small proportion of chlorinated hydrocarbon, for example chlorinated kerosene or chlorinated paraffin wax, may also be desirable. Such chlorinated hydrocarbon may be employed together with an acid alkyl phosphate such as a mixture of mono- and di-lauryl or oleyl phosphates. Other ingredients which may be present in the composition are chloronaphtha ethyl xanthate, di-trichlorobenzyl trithio carbonate, esters such as di (ethylene glycol mono-oleate) malate and halogen-bearing esters. In the examples, phospho-sulphurized esters, prepared by heating glycol dioleate, diethylene glycol dioleate or dithiodiglycol dioleate first with sulphur and then with P4S3 are added to mineral oil. In the case of the phospho-sulphurized glycol dioleate, sulphurization may be effected by means of a mixture of sulphur and S2Cl2, and the glycol dioleate employed may contain some free oleic acid. In another example sulphurized glycol dioleate, prepared by heating glycol dioleate with sulphur, is added to mineral oil, and if desired (a) chlorinated kerosene and a mixture of mono- and di-lauryl phosphates, (b) chlorinated paraffin wax and a mixture of mono- and di-lauryl phosphates or (c) chlorinated kerosene and a mixture of mono- and di-oleyl phosphates are included in the composition. Specification 471,593 is referred to.