Patent GB-1068235-A (GB)
Title: Additives for lubricating compositions
Inventor: ELLIOTT JOHN SCOTCHFORD
IPC: C08F8/32
Filed: 1964-07-09
Abstract: Lubricating compositions comprise a lubricating oil and a minor proportion, sufficient to provide the desired degree of cold sludge dispercency or detergency, of an additive which is the reaction product of (a) a monoalkenyl substituted succinic anhydride wherein the alkenyl group has a molecular weight of at least 700; and (b) a reaction product of dicyandiamide with a primary alkylene polyamine having at least two primary amino groups and containing the group <FORM:1068235/C4-C5/1> where A is 2 to 4.  Preferred additives are obtained by reacting polyisobutylene/maleic anhydride adducts with reaction products of dicyandiamide with polyethylene polyamines, imino bis propylamine and polyethylene imines. The oil may be a mineral oil, solvent refined mineral oil or mixture thereof, or a spindle oil, and the compositions may also comprise copper deactivators, pour point depressants, antioxidants, viscosity index improvers and other conventional additives, particularly zinc dialkyl dithiophosphates, alkaline earth metal petroleum sulphonates, phenates or phenol sulphides, alkaline earth metal salts of phosphosulphurized hydrocarbons, and copolymers of long chain alkyl methacrylates with vinyl pyridine or N-vinyl pyrrolidone. Many examples are given of lubricating compositions comprising mineral oils, reaction products of polyisobutylene succinic anhydride with reaction products of dicyandiamide and triethylene tetramine, diethylene triamine, tetraethylene pentamine, pentaethylene hexamine and imino bis propylamine, together with other additives such as zinc dialkyl dithiophosphates derived from isopropanol and methyl butyl carbinol or from isopropanol and 1-methylheptyl alcohol, barium salts of phosphosulphurized polyisobutylene and alkyl methacrylate copolymers. Example 41 describes a composition of di(2-ethylhexyl) sebacate, an additive of the invention wherein the alkenyl group is polyisobutylene and the amine is tetraethylenepentamine, phenyl-a -naphthylamine, 3,7-dioctyl phenothiazine and benzotriazole.ALSO:An additive for a lubricating oil is a reaction product of (a) a mono alkenyl substituted succinic anhydride wherein the alkenyl group has a molecular weight of at least 700 and (b) a reaction product of dicyandiamide with a primary alkylene polyamine having at least two primary amino groups and containing the group <FORM:1068235/C3/1> where A is 2 to 4. The monoalkenyl substituted succinic anhydride may be obtained by reaction between a normally liquid oil soluble polyolefine having a molecular weight of 700 to 3000 and maleic anhydride.  Reaction product (b) is preferably prepared at a temperature from 240 DEG  to 280 DEG  C. and the molar ratio of (a) to (b) may be from 1:1 to 5:1.  The alkylene polyamine preferably has the formula H2N-(RNH)n-RNH2 where R is an alkylene radical, preferably -CH2CH2- and n is an integer from 1 to 5 or more.  Other alkylene polyamines may also be used e.g. imino bis propylamine; polymerization products of ethylene imine and a mixture of isomeric polyethylene hexamines and related hexamines containing piperazine rings and 12 C atoms. In the examples polyisobutenyl succinic anhydride is prepared either (i) by refluxing polyisobutylene with maleic anhydride and di-t-butyl peroxide in toluene, distilling off toluene, treating with hexane and then distilling off the hexane or (ii) refluxing polyisobutylene with maleic anhydride and then treating with hexane. The products are reacted with reaction products of dicyandiamide and triethylene tetramine, diethylene triamine, tetraethylene pentamine, pentaethylene hexamine and imino bis propylamine.