Abstract: This invention concerns dispersant-VI improvers prepared by reacting a polyamine-derived dispersant with an oxidized ethylene-propylene polymer or ethylene-propylene-diene terpolymer. The products thus formed have a dispersancy superior to that obtained by separately blending the reactants in a lubricating oil. Also disclosed are oils containing the present dispersant-VI improvers.

Abstract: Fatty alkyl succinate ester and succinimide modified copolymers of ethylene and an alpha-olefin, such as an ethylene-propylene copolymer, are useful as shear stable viscosity index (VI) improvers, dispersants and pour point depressants in lubricating oils. Especially useful is the succinate ester of mixtures of primary n-alkanols containing about 12 to about 18 carbon atoms and the N-(3-dimethylaminopropyl) succinimide derivative of the copolymer of ethylene and an alpha-olefin, such as an ethylene-propylene copolymer. This succinate ester-succinimide derivative is prepared by reacting the copolymer in an aromatic solvent with maleic anhydride in the presence of a free radical initiator, then esterifying the anhydride with a fatty alcohol or mixtures thereof in the presence of an acidic catalyst and finally converting any unreacted anhydride and half esters to the succinimide by reaction with a polyamine containing a primary amine. Additive concentrates containing 5 to 30 wt.

Abstract: Disclosed are lubricating oil additives consisting of the reaction product of a di(lower)alkylamino-(lower)akylamine and a hydro-peroxidized ethylene/propylene copolymer having utility as dispersants and viscosity index improvers.

Abstract: The color and viscosity stability of copolymeric .alpha.-olefin viscosity index improvers and of oils containing same are improved by the incorporation therein of minor amounts of N,N'-bis(2-hydroxy-5-alkylbenzyl).alpha.-.OMEGA.-diaminoethane wherein the alkyl group is a C.sub.4 to C.sub.30 alkyl group and the basic metal salts thereof.

Abstract: Novel metal dialkyldithiophosphates prepared from oxalkylated long, straight-chain alcohols, acids and mercaptans and their incorporation in lubricating oils to enhance the lubricity and other properties thereof; and a method for operation of an automatic transmission incorporating said oils.

Abstract: Novel metal dialkyldithiophosphates prepared from oxalkylated long, straight-chain alcohols, acids and mercaptans and their incorporation in lubricating oils to enhance the lubricity and other properties thereof; and a method for operation of an automatic transmission incorporating said oils.

Abstract: Thiadiazole derivative mixture containing as a principal component a product characterized by the formula ##EQU1## where R is alkyl of from 2 to 30 carbons prepared by the method consisting of first contacting 2-amino-5-mercapto-1,3,4-thiadiazole with an alkanal of the formula RCHO where R is a heretofore defined and second contacting the resultant reaction mixture with dimethyl sulfoxide. Lubricating oil composition comprising a hydrocarbon oil of lubricating viscosity containing between about 0.01 and 50 wt. % of said thiadiazole derivative mixture.

Abstract: Thiadiazole derivatives characterized by the formula: ##EQU1## where R is hydrocarbyl of from 1 to 30 carbons and R' is hydrogen or hydrocarbyl of from 1 to 30 carbons prepared by the method of contacting a 2-amino-5-mercapto-1,3,4-thiadiazole characterized by the formula: ##EQU2## sequentially with an alkali metal hydroxide and a hydrocarbyl sulfenyl bromide characterized by the formula R-S-Br where R and R' are as heretofore defined. Hydrocarbon oil compositions comprising a hydrocarbon oil of lubricating viscosity containing between about 0.01 and 50 wt. % of said amino hydrocarbyldithio thiadiazole.