Patent GB-937933-A (GB)
Title: Lubricant additives and lubricant compositions containing them
IPC: C07F9/04
Filed: 1959-11-13
Abstract: A lubricating composition comprises a lubricating oil, especially a hydrocarbon lubricating oil, and an additive combination consisting of an alkaline earth metal-containing phosphorus sulphide-hydrocarbon reaction product and a minor amount by weight of one or more polymeric unsaturated carboxylic acids of average molecular weight of at least 300.  For the preparation of the metal-containing product (see Groups IV(a) and IV(b)).  The polymeric unsaturated carboxylic acid is preferably the commercial acids obtained by the dimerization of linoleic acid and containing (by weight) 85% dilinoleic acid, 12% of tri-linoleic acid and 3% of the monomeric acid.  The incorporation of the polymeric unsaturated carboxylic acid in the alkaline earth metal-containing phosphorus sulphide-hydrocarbon reaction product may be effected at from 100 DEG  to 300 DEG F. and the weight ratios of the said reaction product to polymeric acid may p  be from 20:1 to 10:1.  The combination may also contain 0,1 to 1% by weight of water. Other conventional additives may also be present in the lubricating composition, including metal salts of dialkyldithiophosphates, high molecular weight polybutenes, methacrylate polymers, and condensates of chlorinated paraffin wax and naphthalene.  Specification 744,779 is referred to.ALSO:An alkaline earth metal-containing phosphorus sulphide-hydrocarbon reaction product suitable for use in conjunction with a polymeric unsaturated carboxylic acid of high molecular weight as an additive combination for lubricants (see Group III) is obtained by reacting a normally non-gaseous hydrocarbon, especially a mono-olefin polymer, with a phosphorus sulphide at 150 DEG  to 600 DEG F., hydrolysing the resultant product at 200 DEG  to 500 DEG F., treating the hydrolysed product with a basic alkaline earth metal compound, suitably at 100 DEG  to 500 DEG F., to give an alkaline earth metalcontaining product having an excess alkalinity of at least 2 milligrams NaOH per gram of product and treating the product at 100 DEG  to 400 DEG F. with carbon dioxide to reduce the alkalinity to a value of substantially zero milligram NaOH per gram of product.  The hydrocarbon is preferably a mono-olefin polymer resulting from the polymerization of propylene, a butylene or an amylene or a copolymer obtained by polymerizing a hydrocarbon mixture containing iso-monoolefins or olefin mixtures, e.g. a hydrocarbon mixture containing isobutylene, butylenes and butanes recovered from petroleum gases.  Preferred polymers are those having a molecular weight of from 300 to about 10,000, e.g. a polybutene having a mean molecular weight of about 780-800.  The phosphorus sulphide may be P2S3, P4S3 or P4S7 but is preferably the pentasulphide P2S5.  The phosphosulphurization may be carried out in the presence of a sulphurizing agent, e.g. sulphur, or a sulphur halide and is preferably effected in a non-oxidizing atmosphere, e.g. of nitrogen. The hydrolysis step may be effected by introducing steam through the reaction mass.  Specified basic alkaline earth metal compounds are the oxides and hydroxides of Ba, Ca, Sr or Mg and it is preferred to use the basic compound in the form of a slurry in an oil, e.g. a lubricating oil, and to carry out the reaction in the presence of a mixture of water and a C1-C4 alkanol, e.g. methanol.  The treatment with carbon dioxide is preferably carried out in the presence of 0,1 to about 5% by weight of water.  The polymeric unsaturated carboxylic acid which is used in combination with the alkaline earth metal-containing phosphosulphurized hydrocarbon product is one having an average molecular weight of at least 300 and is preferably an acid obtained by the dimerization of linoleic acid and containing (by weight) about 85% dilinoleic acid, about 12% of trilinoleic acid, and about 3% of the monomeric acid, or is an acid predominating in trilinoleic acid obtained as byproduct in the manufacture of sebacic acid by the distillation of castor oil in the presence of caustic alkali.  The incorporation of the polymeric unsaturated carboxylic acid in the alkaline earth metal-containing phosphorus compound may be effected at from 100 DEG  to 300 DEG F.  Specification 744,779 is referred to.ALSO:An alkaline earth metal-containing phosphorus sulphide-hydrocarbon reaction product suitable for use in conjunction with polymeric unsaturated carboxylic acids of high molecular weight as an additive combination for lubricants (see Group III) is obtained by reacting a normally non-gaseous hydrocarbon with a phosphorus sulphide at 150 to 600 DEG F., hydrolysing the resultant product at 200 DEG  to 500 DEG F., treating the hydrolysed product with a basic alkaline earth metal compound, suitably at 100 DEG  to 500 DEG F., to give an alkaline earth metal-containing product having an excess alkalinity of at least 2 milligrams NaOH per gram of product and treating the product at from 100 DEG F. to 400 DEG F. with carbon dioxide to reduce the alkalinity to a value of substantially zero milligram NaOH per gram of product.  The hydrocarbon is preferably a mono-olefin polymer (see Group IV(a)) but other suitable hydrocarbons are essentially hydrocarbons, e.g. bright stock residuums, lubricating oil distillates, petrolatums, or paraffin waxes. Olefines having at least 20 carbon atoms in the molecule of which from 13 to 18 carbon atoms are in a straight chain, aromatic hydrocarbons, and alkylated aromatic hydrocarbons are also suitable. The phosphorus sulphide may be P2S3, P4S3 or P4S7 but is preferably phosphorus pentasulphide P2S5.  The phosphosulphurisation may be carried out in the presence of a sulphurising agent, e.g. sulphur or a sulphur halide and is preferably effected in a non-oxidising atmosphere, e.g. of nitrogen.  The hydrolysis step may be effected by introducing steam through the reaction mass.  Specified alkaline earth compounds for reacting with the hydrolysed product are the oxides and hydroxides of Ba, Ca, Sr or Mg and it is preferred to use the basic reagent in the form of a slurry in an oil, e.g. a lubricating oil and to carry out the reaction in the presence of a mixture of water and a C1-C4 alkanol, e.g. methanol. The treatment with carbon dioxide is preferably carried out in the presence of 0,1 to about 5% by weight of water.  The polymeric unsaturated carboxylic acid is one having a molecular weight of at least 300, e.g. one predominating in di- or trilinoleic acid and the incorporation of the acid in the alkaline earth metal-containing phosphorus product may be effected at from 100 DEG F. to 300 DEG F.  Specification 744,779 is referred to.