Abstract: Combinations of carboxylic solubilizers, made by reaction of an acylating agent with an N-(hydroxyl-substituted hydrocarbyl) amine and surfactants are useful in incorporating oil-soluble, water-insoluble functional additives into aqueous systems. Typical solubilizers are made by reacting an alkyl-substituted succinic anhydride containing about 12 to about 500 carbon atoms with an alkanol amine such as diethyl ethanol amine. Typical surfactants are nonionic hydrophilic surfactants such as ethoxylated phenols and ionic surfactants of both the anionic and cationic type. Typical functional additives are anti-wear, extreme pressure and load-carrying agents such as dithiophosphates. The aqueous systems formed with the aid of such combinations are useful, for example, as water-based hydraulic fluids.

Abstract: Nitrogen-containing phosphorus-free carboxylic acid derivatives made by reaction of an acylating agent with an alkanol tertiary monoamine are described. Typically the carboxylic acylating agent is an alkyl or alkenyl succinic anhydride containing about 20 to about 500 carbon atoms in the alkyl or alkenyl group. A typical amine is diethyl ethanol amine. These derivatives are useful in incorporating oil-soluble, water-insoluble functional additives, such as metal salts of acid phosphate and thiophosphate hydrocarbyl esters, into water-based functional fluids such as water-based hydraulic fluids.