Ethylene alpha-olefin Mannich Base viscosity index improver/dispersant additives derived from amino phenols and monosecondary amines

A lubricating oil additive which comprises a Mannich base condensation product obtained by:

• (i) providing N-hydroxyaryl amine-containing Mannich base intermediate obtained by reacting at least one N-hydroxyaryl amine compound, at least one aldehyde reactant and at least one monosecondary amine reactant containing at least one amine of the formula ##STR33## wherein R and R' are the same or different and are alkyl, cycloalkyl, aryl, alkaryl, aralkyl, and derivatives of the foregoing groups containing one or more tertiary amine groups, wherein R and R' independently contain from 1 to 50 carbon atoms, said N-hydroxyaryl amine-containing Mannich base intermediate containing at least one primary amine group and at least one moiety of the formula ##STR34## wherein a is an integer of 1 or 2, R and R' are the same or different and are alkyl, cycloalkyl, aryl, alkaryl, aralkyl and hydrocarbyl substituted derivatives thereof, and derivatives of the foregoing groups containing carbon substitution by one or more tertiary amine groups, one or more oxygen, nitrogen, or sulfur atoms, wherein R and R' contain from 1 to 50 carbon atoms, A' comprises the group --CH(T")-- wherein T" is H or alkyl of from 1 to 9 carbon atoms and is derived from said aldehyde reactant, and Ar" comprises the moiety of the formula ##STR35## wherein T' is hydrogen, alkyl having from 1 to 3 carbon atoms or halogen and Ar represents ##STR36## and wherein r" is 1 or 2, and derivatives thereof wherein from 1 to 3 ring carbon atoms are such substituted by a alkyl group or halogen atom;
• and
• (ii) contacting said N-hydroxyaryl amine-containing Mannich base intermediate with at least one reaction product of an oil-soluble ethylene copolymer comprising from about 15 to 90 wt % ethylene and about 10 to 85 wt % of at least one C.sub.3 to C.sub.28 alpha-olefin, said copolymer having a number average molecular weight of from greater than about 10,000 to 500,000, and grafted with an ethylenically unsaturated carboxylic acid material having 1 to 2 dicarboxylic acid groups or anhydride groups for a time and under conditions sufficient to form said Mannich base condensation dispersant product.