A thermoplastic molding composition containing A) 20 to 99.9 wt % of a thermoplastic polyamide, B) 0.1 to 40 wt % of an alkenylsuccinic acid derivative obtained by reaction of polyiso-butene (B1) having a number-average molecular weight Mn of 10,000 to 50,000 at temperatures of 180° C. to 250° C. with maleic acid or derivatives thereof (B2) in a stoichiometric ratio of at least 2 equivalents of α,β-unsaturated mono- and dicarboxylic acid or derivatives thereof (B2) per reactive double bond in the polyisobutene (B1) for a duration of at least 15 minutes to 10 hours and up to 10 bar of positive pressure, wherein the derivatives are anhydrides, mono- or dialkyl esters, and mixed esters, and wherein the reactive double bonds are the sum total of the terminal α- and β-double bonds in the polyisobutene (B1), and C) 0 to 60 wt % of further additives, wherein the weight percentages for the components A) to C) sum to 100%.