Patent GB-749443-A (GB)
Title: Improvements in or relating to lubricant compositions containing metal-containing lubricant additives
IPC: C10L1/24
Filed: 1953-02-11
Abstract: Metal salts of compounds having the general formula <FORM:0749443/IV(a)/1> wherein X is either oxygen or sulphur and R, R1 and R2 are either hydrogen or a hydrocarbon radical containing from 1 to 25 carbon atoms for use in lubricating compositions (see Group III) are prepared by mixing organic acids or acid chlorides with p-aminophenol or the alkylated derivatives or the corresponding thiophenolic compounds, heating the mixture to bring about reaction and reacting the product with a metal, metallic oxide, hydroxide, sulphide, alkoxide, hydride or carbide.  The heavy metal compounds may also be prepared by double decomposition between alkali metal salts of the acyl amino phenols and heavy metal salts.  The acyl amino phenolic compounds are usually converted to the salts at elevated temperature and in the presence of an inert solvent, e.g. chloroform, isopropyl alcohol or in a synthetic or mineral lubricating oil.  When a lubricating oil is employed anti-foaming agents may be added, e.g. stearyl, lauryl, cetyl and wool fat alcohols.  Salts mentioned include those of alkali metals, barium, calcium, strontium, aluminium, copper, cobalt, antimony, tin, zinc, iron and nickel.  Basic or neutral salts and mixtures of salts may be formed.  The hydrocarbon radicals from which R, R1 and R2 may be chosen include alkyl, alkenyl, cycloalkyl, alkaryl and aliphatic, alicyclic and aromatic radicals.  Straight or branched chain alkyl radicals are preferred, e.g. methyl, isopropyl, tert. amyl, tert. octyl, n-decyl, dodecyl and cetyl and other radicals mentioned include hexenyl, nonenyl and oleyl, cyclohexyl, n-butylcyclohexyl, phenyl, diethyl- and butyl phenyl radicals.  Aminophenols and thiophenols which may be acylated include p-aminophenol, 3-hexyl, 2-tert. amyl-, 2-tert. octyl-, 2,6-di-tert. octyl-3-pentadecyl, 2-isohexadecyl and C16-C10 branched chain alkyl-4-aminophenols and 3-hexyl-, 2-tert. hexyl- and 3-hexadecyl-4-amino thiophenols.  These phenols and thiophenols may be acylated with fatty acids and highly branched oxo acids such as formic, acetic, butyric, caprylic, capric, lauric, palmitic, stearic, undecylenic, oleic, linoleic, cyclohexyl valeric, 7,7,9,9-tetramethyldecanoic and 6,8,8,10,10-pentamethyl undecanoic acids and naphthenic acids.  The oxo acids are prepared by the oxidation of oxo alcohols.  Specific products include the lithium salt of an N-C8 oxo acyl-4-aminophenol; sodium, lithium and basic barium salts of an N-C13 oxo acyl 4-aminophenol, normal barium salts of N-C8 oxo acyl- and N-C13 oxo acyl-3-pentadecyl-4-aminophenol and the normal barium, calcium and strontium salts of N-lauroyl-4-aminophenol. Specification 693,851 is referred to.ALSO:A composition comprises a lubricating oil and a minor prorportion of a metal salt of a compound having the general formula <FORM:0749443/III/1> wherein X is either oxygen or sulphur and R, R1 and R2 are either hydrogen or a hydrocarbon radical containing from 1 to 25 carbon atoms.  The hydrocarbon radicals may be alkyl, alkenyl, cycloalkyl, alkaryl and aliphatic, alicyclic or aromatic generally. Straight or branched chain alkyl radicals are preferred, e.g. methyl, isopropyl, tert. amyl, tert. octyl, n-decyl, dodecyl and cetyl and other radicals mentioned include hexenyl, nonenyl, oleyl, cyclohexyl, ethyl cyclohexyl, n-butylcyclohexyl, unsaturated cycloaliphatic radicals, phenyl, methyl phenyl, butyl phenyl and diethyl phenyl radicals. Preferably R has from 6 to 20 carbon atoms and R1 and R2 not more than a total of 30 carbon atoms.  Preferably at least one of R1 and R2 is hydrogen.  Aminophenols and thiophenols from which additives may be prepared include p-aminophenol, 3-hexyl-2-tert.-amyl-, 2-tert.-octyl, 2, 6-di-tert.-octyl, 3-pentadecyl-2-isohexadecyl- and C16-C20 branched chain alkyl-4-aminophenols, and 3-hexyl-, 2-tert.-hexyl-, and 3-hexadecyl-4-aminothiophenols. The phenols and thiophenols may be acylated with fatty acids or highly branched oxo acids such as formic, acetic, butyric, caprylic, capric, lauric, palmitic, stearic, undecylenic, oleic, linoleic, cyclohexylvaleric, 7, 7, 9, 9-tetramethyl decanoic, 6, 8, 8, 10, 10-pentamethyl undecanoic and naphthenic acids.  The oxo acids are prepared by oxidizing oxo alcohols.  The acyl aminophenols are converted to metal salts by reaction with appropriate metal compounds (see Group IV(b)).  When the additives are prepared in synthetic or mineral oil, antifoaming agents such as higher alcohols, e.g. stearyl, lauryl, or cetyl or wool fat alcohols may be added to the reaction mixture.  Monovalent metal salts, e.g. of sodium, potassium and lithium, are suitable as thickening agents or antioxidants.  Polyvalent metal salts are prepared, e.g. salts of barium, calcium, strontium, aluminium, copper, cobalt, antimony, zinc, tin, iron, nickel and other heavy metals.  Normal or basic salts may be employed as may be mixtures of metal salts, prepared with two or more basic neutralizing agents, e.g. lime and barium hydroxide.  In examples: Compositions are prepared comprising a mineral lubricating oil or a synthetic lubricant, a complex ester formed by reacting adipic acid, 1, 3-butanediol and a C8 oxo alcohol, and an N-C8 oxo acyl-4-aminophenol lithium salt, N-C13 oxo acyl-4-aminophenol sodium, lithium and basic barium salts, an N-C8- oxo acyl-3-pentadecyl-4-aminophenol and the normal barium salts an N-C13- oxo acyl-3-pentadecyl-4-aminophenol normal barium salt and N - lauroyl - 4 - aminophenol normal barium and strontium salts and the free N-acylated phenols(I); mineral oil and C13 oxo acyl - 3 - pentadecyl - 4 aminophenol barium salt (II); mineral oil and barium, calcium, strontium, sodium and lithium salts of C13-C20 acyl amino phenols (III); and greases are prepared by heating together rapeseed oil, sodium hydroxide, petroleum sulphonate and a coastal distillate alone and together with the basic barium salt of a C13 oxo acyl 3- pentadecyl -4-aminophenol or with N-lauroyl-p-aminophenol (IV).  Lubricating oil stocks which may be used in the compositions include straight mineral oils, residuals, e.g. from which asphalte constituents have been removed, hydrogenated oils or white oils, synthetic oils, e.g prepared by the polymerization of olefines or the reaction of oxides of carbon with hydrogen or by the hydrogenation of coal or its products, cracking coal tar fractions, coal tar or shale oil distillates.  Animal, vegetable or fish oils or their hydrogenated or voltolized products may be employed alone or in admixture with mineral oils.  Other synthetic lubricants mentioned include long chain esters of mono-basic acids, polybasic acids, mono- and polyhydroxy alcohols polymerized esters, ethers or ether-esters.  In addition, dyes, pour depressors, heat thickened fatty oils, organometallic compounds, metallic or orther soaps, slude dispersers, antioxidants, thickeners, viscosity index improvers, oiliness agents, resins, rubber, olefin polymers, voltolized fatty oils or fats or mineral oils and/or voltolized waxes and colloidal solids such as graphite or zinc oxide may be added to the compositions.  Lubricating greases may be prepared by dispersing common greasemaking soaps in lubricating oil, e.g. soaps of alkaline earth or alkali metals such as calcium, strontium, barium, potassium, sodium or lithium formed with hydrogenated fish oil acids, stearic acid, hydroxy stearic acid, oleic acid, palmitic acid, lauric acid, tallow, coconut oil, the saturated or unsaturated glycerides of the various fatty acids or mixtures thereof.  The oil base in the grease may be a mineral oil distillate or synthetic lubricating oil.  Specification 693,851 is referred to.