GB660110A - Improvements in or relating to the preparation of lubricants and compositions containing the same - Google Patents

Abstract

Synthetic lubricants are prepared by reacting an aliphatic ether having two olefinic radicals attached to the ether oxygen atom with hydrogen sulphide or a mercaptan and thereafter removing volatile components from the product by distillation under reduced pressure until the remaining product has a boiling-point equivalent to at least 160 DEG C. under 0.2 cm. mercury pressure. This distillation may be effected under any reduced pressure providing that it is continued until the boiling-point of the remaining product has risen to the equivalent of 160 DEG C. under 0.2 cm. mercury pressure. The interaction of the olefinic and sulphur compounds may be effected in presence of ultra-violet light, peroxides, air or oxygen resulting in adducts formed by abnormal addition, or in presence of aluminium chloride, silicon tetrachloride or basic catalysts, e.g. alkali metal or alkaline earth metal hydroxides, primary, secondary or tertiary amines, pyridine or piperidine. Reaction temperatures of up to 150 DEG C. may be used. The reactants are preferably employed in the ratio of between 0.5 to 2 mols. of olefinic ether per mol. hydrogen sulphide or mercaptan. Diluents such as saturated hydrocarbons may be present. Olefinic ethers mentioned are divinyl ether, diisopropyl ether, diallyl ether, dicrotyl ether, dimethallyl ether, di-(a -methyl allyl) ether, (1 - butene - 3 - yl) - (2 - butene - 4 - yl) ether, dihexenyl ether, allyl-(2-methyl-4-pentene-2-yl) ether, allyl linalyl ether and halogenated derivatives of the type of hexachlor-divinyl ether. The mercaptans used may be aliphatic, and are preferably the normal or iso-alkyl chain mercaptans of primary, secondary or tertiary character; methyl, ethyl, butyl, amyl, hexyl, heptyl and octyl mercaptans and polymethylene dimercaptans are mentioned. In examples: (1) Hydrogen sulphide and diallyl ether in equimolar amounts are subjected to ultra-violet light in a sealed evacuated quartz bomb and in liquid state and the product distilled to 235 DEG C. under 2.3 cms. pressure; (2) hydrogen sulphide and dimethyallyl ether are similarly reacted and the product distilled to 240 DEG C. at about 2 cms. pressure; (3) di-(b -mercapto ethyl) ether and diallyl ether are similarly reacted, the product being distilled up to 240 DEG C. under 8 mms. pressure; (4) hydrogen sulphide (0.28 mol.) is bubbled into 180 ccs. divinyl ether in an irradiated flask at 0 DEG C. and the product distilled up to 240 DEG C. under 1 cm. pressure; (5) hydrogen sulphide and diallyl ether in equimolar amounts are heated in presence of di-t.-butyl peroxide in an autoclave at 100 DEG C. and the product distilled up to 240 DEG C. under 0.2 cm. pressure. Specification 558,790 is referred to. The Specification as open to inspection under Sect. 91 relates to the production of lubricants by reacting an organic compound having at least one unsaturated linkage between two carbon atoms of aliphatic nature with hydrogen sulphide or a mercaptan and separating from the product the material volatilizing at relatively low temperatures. The unsaturated reagents mentioned include olefines, dienes, acetylenes, ethers and thioethers; some may contain such substituents as alkoxy, aryloxy and aralkoxy groups or chlorine and other halogen atoms. Numerous examples are given. Products containing terminal hydroxy groups may be etherified or esterified and many agents for this purpose are given, including hydroxy-and carboxy-alkylating agents. In a further example, allyl alcohol and hydrogen sulphide are heated in an autoclave in presence of di-n-butylamine and the product distilled up to 134 DEG C. at 0.3 cm. pressure, the lubricating portion being bis-(b -hydroxy-a -methyl-ethyl) sulphide; a by-product is b -hydroxy-a -methyl-ethyl mercaptan. This subject-matter does not appear in the Specification as accepted.ALSO:Synthetic lubricants comprise the products obtained by reacting an aliphatic ether having two olefinic radicals attached to the ether oxygen atom with hydrogen sulphide or a mercaptan and thereafter removing volatile components from the priduct by distillation under reduced pressure until the remaining product has a boiling point equivalent to at least 160 DEG C. under 0.2 cm. mercury (see Group IVb). Distillation may be effected under any convenient reduced pressure providing that it is continued until the boiling point of the remaining product has risen to the equivalent of 160 DEG C. under 0.2 cm. pressure. They may be used compounded with minor amounts of metallic soaps or other gelling agents, corrosion inhibitors such as organic acids capable of forming water-insoluble metallic soaps, anti-oxidants such as 1, 2-dihydroxy benzene, extreme pressure additives and other lubricants such as alkylene oxide or glycol polymers. They may be used for low temperature and extreme pressure lubrication; their use in hypoid gear lubricants, cutting oil compositions and metal drawing compounds is mentioned. Examples describe products derived from (1) diallyl ether, dimethallyl and divinyl ether respectively and hydrogen sulphide and (2) diallyl ether and di-(b -mercapto ethyl) ether. Other starting materials, are mentioned including hexachlor-divinyl ether. The Specification as open to inspection under Sect. 91 relates to synthetic lubricants obtained by reacting any organic compound having at least one unsaturated linkage between two carbon atoms of aliphatic nature with hydrogen sulphide or a mercaptan and removing from the product the material which volatilizes at relatively low temperatures. The unsaturated reagents are stated to include olefines, dienes, acetylenes, ethers and thioethers and many examples are given. The synthetic lubricants include those products having terminal hydroxyl groups which have been etherified or esterified by organic or inorganic acids; many etherifying and esterifying agents are mentioned. An additional example describes a product derived from allyl alcohol and hydrogen sulphide and said to be bis (b -hydroxy a methyl ethyl) sulphide; the wear characteristics of the di-2-ethyl hexoate of bis (gammahydroxy propyl) sulphide are given. This subject-matter does not appear in the Specification as accepted.