The reaction product of (i) an oligomer formed from one monomer or two or more different monomers, the or each monomer being an ethylenically unsaturated compound and said oligomer or each of said monomers being optionally partially or fully esterified, with (ii) a polyalkenyl derivative of an ethylenically unsaturated carboxylic reagent (iii), and (iv) a polyamine containing at least two --NH.sub.2 and/or --NH groups, wherein at least one of the ethylenically unsaturated compounds of the oligomer has a functional group which can react with an amine; and the use of the reaction product for its dispercency and low haze properties in lubricant compositions, fuel compositions and additive concentrates.