GB1040896A - Dithiophosphates - Google Patents

Abstract

A lubricating oil or hydrocarbon fuel composition comprises a major proportion of a lubricating oil or hydrocarbon fuel and a minor proportion, sufficient to inhibit oxidation of said oil of a dialkyl phenyldithiophosphate salt of a polyethylene polyamine, wherein the alkyl groups contain from 8 to 18 carbon atoms each and said polyethylene polyamines contain not more than 5 ethylene amine units (see Division C2). It may be used in combination with non-metallic ashless detergents such as copolymers containing polyglycol groups of the type described in Specification 917,923; nitrogen containing ashless detergents derived from alkenyl succinic anhydrides containing 30 or more carbon atoms in the alkenyl group and amine compounds such as tetrathylene pentamine, N-aminoethyl piperazine, and dimethyl amino-propylamine. The lubricant compositions may also contain detergents, viscosity improving agents, rust inhibitors, oiliness agents and other oxidation and corrosion inhibitors. The lubricating oils may be synthetic oils such as polymers of propylene, butylene, propylene oxide polymers, dicarboxylic esters and silicon esters. Fuel oils used as base oil include hydrocarbon base fuels which may also contain additives such as antiknock agents, ignition promoters, gum inhibitors and detergents.ALSO:The invention comprises dialkylphenyldithiophosphate salts of polyethylene polyamines, wherein the alkyl groups contain from 8 to 18 carbon atoms each and said polyethylene polyamines contain not more than 5 ethylene amine units. They may be obtained by neutralizing a dialkylphenyldithiophosphoric acid with the appropriate polyethylene polyamine. The neutralization may be carried out by either a batch process or continous process involving recycle of excess reactant. Specified dithiophosphoric acids are di(octylphenyl)-, octylphenyl dodecylphenyl-, di(nonylphenyl)-, nonylphenyl dodecylphenyl-, di(dodecylphenyl)-, di(hexadecylphenyl)- and di(octadecylphenyl)-dithiophosphoric acids. Specified polyethylene polyamines are diethylene triamine, triethylene tetramine, tetraethylene pentamine, pentaethylene hexamine and mixtures thereof. Examples are given for the preparation of mono-, di- and tri-salts of didodecyl-phenyl -dithiophosphoric acid and triethylene tetramine, and tri and penta salts of didodecylphenyldithiophosphoric acid and tetraethylene pentamine. They may be used as inhibitors for lubricant and fuel compositions (see Division C5). The dialkyl dithiophosphoric acids may be prepared by reaction of the appropriate alkyl phenols or their mixtures with phosphorus sulphides such as P2S5. Particularly suitable dialkylphenyl dithiophosphoric acids are those prepared from alkyl phenols in which the alkyl group has an average of 12 carbon atoms and is derived from a propylene polymer.