Patent GB-755170-A (GB)
Title: Improvements in or relating to lubricating oil additive having improved copper corrosion properties
IPC: C10L1/26
Filed: 1954-08-10
Abstract: Phospho-sulphurized metal salts of alkyl phenol sulphides are prepared by heating a sulphide of phosphorus in a mol. ratio of less than 0.25 : 1.0 at 100-200 DEG  C. with a metal alkyl phenol sulphide containing less than 0.3 per cent by weight of water. The reaction may be conducted in a solvent such as a mineral oil or a hydrocarbon, such as xylol.  The phosphorus sulphides specified are the pentasulphide (P2S5), the trisulphide (P4S3) or the heptasulphide (P4S7).  The metal alkyl phenol sulphide may have the general formula <FORM:0755170/IV(a)/1> where R is one or more alkyl groups each containing from 5 to 25 carbon atoms such as t.-octyl- and t.-amyl-, M is a metal and x is an integer between 1 and 4.  Metal alkyl phenol sulphides specified are those of alkaline-earth metals such as barium, calcium or strontium or of mixtures thereof such as calcium tert.-octyl phenol sulphide, barium-2:4-di-tert.-amyl phenol sulphide, strontium tert.-amyl phenol sulphide and the mixed calcium-barium tert.-octyl phenol sulphide.  After the reaction with phosphorus sulphide, the reaction mixture is filtered and nitrogen is blown through at 100-120 DEG  C. to remove unwanted products and to yield a solution of the product which may be added as an antioxidant and detergent to mineral oils and motor fuels (see Group III), to natural or synthetic rubber, asphalts, road oils and waxes (see Group V), and in organic materials generally. Examples illustrate the effect on the characteristics of the product of the use of various mol. ratios of phosphorus sulphide and metal alkyl phenol sulphide and of various degrees of dryness of the metal alkyl phenol sulphide. Metal alkyl phenol sulphides.-The metal alkyl phenol sulphides are prepared by adding the corresponding metal or metallic oxide, hydroxide or sulphide at an elevated temperature to a mineral oil solution of the alkyl phenol sulphide.  The solution may contain sufficient higher alcohol as an anti-foaming agent to give a concentration of 2-15 per cent of alcohol in the final metal salt concentrate.  Alcohols specified are stearyl, lauryl, cetyl or wool fat alcohol or hydrogenated coconut oil alcohol.  Water is removed by blowing nitrogen through the solution at a temperature above 100 DEG C. until the water content is below 0.3 per cent by weight.  In an example, barium hydroxide octahydrate is added to a solution of tert.-octyl phenol sulphide in higher alcohols and mineral lubricating oil at 120 DEG  C. until neutralized, the reaction mixture filtered and blown with nitrogen to give an oil concentrate containing 40 per cent barium tert.-octyl phenol sulphide. ALSO: Lubricating oils, motor fuels, heating oils, cutting oils, turbine oils, transformer oils, gear lubricants and greases are described containing as antioxidants and detergents phospho-sulphurized metal alkyl phenol sulphides prepared by reacting a phosphorus sulphide at 100-200 DEG C. in a mol ratio of less than 0.25 : 1.0 with a metal alkyl phenol sulphide containing less than 0.3 per cent by weight of water and which may contain higher alcohols such as stearyl, lauryl, cetyl, wool fat alcohol, or alcohol from hydrogenated coconut oil (see Group IV(b). Lubricating oil base stocks which may be used include those derived from petroleum distillates and residuals, hydrogenated oils, white oils, synthetic oils prepared by polymerization of olefines, by reaction of oxides of carbon with hydrogen or by hydrogenation of coal, and synthetic polyether and polyester-type lubricants either as such or blended with mineral lubricants.  The additives may be used in combination with alkaline-earth metal petroleum sulphonates, pour point depressors, viscosity index improvers and thickening agents.  Examples describe various mineral lubricating oil concentrates containing phospho-sulphurized barium tert-octyl phenol sulphide. ALSO: Phospho-sulphurized metal alkyl phenol sulphides prepared by reacting a phosphorus sulphide at 100-200 DEG C. in a mol ratio of less than 0.25 : 1.0 with a metal alkyl phenol sulphide containing less than 0.3 per cent by weight of water and which may also contain higher alcohols such as stearyl, lauryl, cetyl, wool fat alcohol or alcohol obtained from hydrogenated coconut oil (see Group IV(b)) are employed as antioxidant additives in asphalts, road oils, waxes and fatty oils of animal or vegetable origin. They may also be used in natural and synthetic rubber compounds both as vulcanization systems and as antioxidants.