| abstract |
The invention provides a composition comprising: (A) at least one dicarboxylic acid or anhydride or at least one ammonium or metal salt of the dicarboxylic acid or anydride; and (B) at least one compound represented by the formula <CHEM> wherein R2, R3, R4 and R5 are each independently hydrogen, alkyl, hydroxyalkyl, polyhydroxyalkyl, polyalkoxyalkyl or hydroxypolyalkoxyalkyl; and R1 is a hydrocarbyl group. In another embodiment, the compositions include (C) at least one acid, or ammonium or metal salt of the acid represented by the formula: <CHEM> wherein R6, R7, R8 and R9 are each independently hydrogen or hydrocarbyl groups; and n is a number from 1 to about 10; (D) at least one ester-salt derived from at least alkyl or alkenyl succinic acid or anhydride of about 8 to about 28 carbon atoms and at least one alkanol amine; or mixtures of (C) and (D). The invention further provides for concentrates and functional fluids containing the above corrosion-inhibitors. |