Patent GB-851588-A (GB)
Title: Lubricating oil compositions
IPC: C10M161/00
Filed: 1959-05-15
Abstract: An oil-soluble poly-substituted alkane having a plurality of cyclic amido groups and a plurality of alkoxy formyl groups <FORM:0851588/IV(a)/1> , wherein R is an alkyl group containing at least 8 carbon atoms, said groups being attached to separate carbon atoms of the alkane chain, is employed as an ingredient of a lubricating oil composition (see Group III).  The poly-substituted alkane may be a copolymer of (i) one or more vinyl lactam (e.g. vinyl pyrrolidones or vinyl piperidones) and (ii) one or more esters formed between aliphatic alcohols having at least 8 carbon atoms and alpha, beta-unsaturated aliphatic carboxylic acids (e.g. alkyl esters of acrylic and methacrylic acids).  Monomers (i) and (ii) may be copolymerized with (iii) an ester formed between a C1-C5 aliphatic alcohol and an alpha, betaunsaturated aliphatic carboxylic acid (e.g. a lower alkyl ester of acrylic or methacrylic acid).  The preparation is described of N-vinyl pyrrolidone/lauryl methacrylate copolymer, N-vinyl pyrrolidone/lauryl methacrylate/stearyl methacrylate copolymer and N-vinyl piperidone/stearyl methacrylate copolymer.ALSO:A lubricating composition (particularly an engine lubricant of improved detergency, oxidation stability, storage stability and colour stability and also having improved wearpreventive properties) comprises a major proportion of a hydrocarbon lubricating oil and minor proportions of (a) an oil-soluble polysubstituted alkane having a plurality of cyclic amido groups and a plurality of alkoxyformyl groups <FORM:0851588/III/1> , wherein R is an alkyl group containing at least 8 carbon atoms, said groups being attached to separate carbon atoms of the alkane chain, and (b) a p,p1-methylene bisphenol, or a monoether thereof, of formula:  <FORM:0851588/III/2> where R1 is hydrogen or a hydrocarbyl radicale and the R11s are tertiary alkyl radicals which may be the same or different.  The lubricating oil may be a mineral oil or a synthetic oil (e.g. a polymerized olefin such as polyisobutylene), but may be blended with a minor proportion of fatty oil (e.g. castor oil or lard oil).  Ingredient (a) may be a copolymer of (i) one or more vinyl lactams (e.g. vinyl pyrrolidones or vinyl piperidones) and (ii) one or more esters formed between aliphatic alcohols having at least 8 carbon atoms and alpha, betaunsaturated aliphatic carboxylic acids (e.g. alkyl esters of acrylic and methacrylic acids).  Monomers (i) and (ii) may be copolymerized with (iii) an ester formed between a C1-C5 aliphatic alcohol and an alpha, beta-unsaturated aliphatic carboxylic acid (e.g. a lower alkyl ester of acrylic or methacrylic acid).  The lubricating composition may also contain a minor proportion of a partial or full ester of an acid of phosphorus (e.g. a phosphite, phosphate or phosphonate ester, including chlorinecontaining phosphonates such as dibutyl trichloromethane phosphonate, or the esters p  derived from the corresponding thio-acids of phosphorus), or a small quantity of an antifoam agent (e.g. a silicone polymer.  In the examples, mineral lubricating oil compositions are described in which ingredient (a) is N-vinyl pyrrolidone/lauryl or octyl methacrylate copolymer or (N-vinyl pyrrolidone or N-vinyl-3-methyl pyrrolidone)/stearyl methacrylate/lauryl methacrylate copolymer and ingredient (b) is 4,41-methylene bis (2,6- or 3,5-di-tert. butyl phenol, 4,41-methylene bis (2,6-di-tert. octyl phenol) or 4,41-methylene bis (2-tert. butyl-6-tert. octyl phenol).  In some instances, the composition also contains dimethyl silicone polymer and/or tricresyl phosphate.  The effect is described of omitting ingredient (a) or (b), or of replacing ingredient (b) by 2,21-methylene bis (4-methyl-6-tert. butyl phenol), 4,41-methyllene bis (2-methyl or isopropyl-6-tert. butyl phenol), 4,41-methylene bis (2,6-diisopropyl phenol), 2,6-di-tert. butyl-4-methyl phenol, propyl dodecyl sulphide or phenyl alpha naphthylamine.