Patent GB-810685-A (GB)
Title: Lubricating oil compositions
IPC: C10M165/00
Filed: 1956-09-24
Abstract: A lubricating composition, suitable for use as an engine oil, turbine oil or gear oil, comprises a major proportion of a lubricating oil and minor proportions of (1) an oil-soluble polymeric compound as defined below, and (2) an oil-soluble neutral or basic metal salt of a carbocyclic carboxylic acid. Ingredient (1) has a molecular weight of at least 1000 and a linear hydrocarbon chain bearing a plurality of the same or different polar and non-polar groups.  The polar groups are groups consisting of or containing -OR, -OOCR, -OCOOR, -COOR, -SCN, -CN, -CONR, -COONR or a heterocyclic nitrogen-containing group (R being hydrogen, an alkyl group of either 4 carbon atoms or less at 8 carbon atoms or more, or an aliphatic basic nitrogen-containing group), while the non-polar groups are hydrocarbon groups containing at least 8 carbon atoms.  Polymeric compounds suitable as ingredient (1) are (a) copolymers of alpha-olefins with acrylic compounds (e.g. acrylic acid, acrylamide, acrylonitrile and the corresponding methacrylic compounds); (b) copolymers of alpha-olefins with vinyl halides or esters (e.g. vinyl chloride or acetate), which copolymers have been after-treated to convert the halide or ester groups to -OH groups; (c) copolymers of polymerizable heterocyclic nitrogen-base compounds (e.g. vinyl pyridines and alkyl-substituted vinyl pyridines) with polymerizable unsaturated materials free of heterocyclic nitrogen-containing radicles (e.g. acrylic acid and alpha-substituted acrylic acids and their esters, nitriles and amides); and (d) copolymers of acrylic or alpha-alkyl-substituted acrylic esters of alkyl tertiary amino alkanols with the corresponding esters of other saturated aliphatic alcohols.  Ingredient (2) may be a calcium, barium, strontium or magnesium salt of a naphthenic acid or of an unsubstituted or alkyl-substituted benzoic, salicylic, resorcylic, anthranilic or naphthoic acid.  The lubricating composition may also contain antioxidants, corrosion inhibitors, viscosity index improvers and pour point depressants.  Specific additional materials which may be present include organic phosphates and thiophosphates, other phosphorized, phosphosulphurized or phosphoselenized organic materials, metal salts of these, metal alkyl dithiocarbamates, amines, "Acryloid" polymers, naphthalene-chlorinated paraffin wax condensates, trichloromethane phosphonic acid and its esters, amides and amine salts, and organic sulphides.  The lubricating oil employed in the lubricating composition may be mineral or synthetic or a mixture of both and may be blended with fatty oils.  Synthetic lubricating oils mentioned are polymerized olefins, copolymers of alkylene glycols and oxides, esters (e.g. di-2-ethyl hexyl sebacate, dioctyl phthalate and trioctyl phosphate), polymeric tetrahydrofuran and polyalkyl silicone polymers.  In the examples, mineral lubricating oil compositions are described in which ingredient (1) is lauryl methacrylate/diethylaminoethyl methacrylate copolymer, lauryl or octadecyl methacrylate/2 - methyl - 5 - vinylpyridine copolymer, hydrolysed hexadecene-1 or octadecene-1/vinyl acetate copolymer, lauryl methacrylate/styrene/dibutylamino ethyl methacrylate copolymer, lauryl methacrylate/4-dimethyl - amino - cyclohexyl methacrylamide copolymer, lauryl methacrylate/2-ethyl-5-vinyl pyridine copolymer or lauryl methacrylamide/2-methyl - 5 - vinylpyridine copolymer, and ingredient (2) is neutral and/or basic calcium, barium or zinc alkyl salicylate or alkyl benzoate or basic calcium naphthenate.  Zinc dimethyl cyclohexyl thiophosphate may be present as an additional ingredient. Specifications 777,773 and 799,037 are referred to.