A method of use of copolymers containing fluoro groups and hydroxyl groups as additives in powder coating materials, comprising mixing these component with powder coatings resins, the copolymers comprising units of the following monomers: olefinically unsaturated monomers having from 5 to 40 carbon atoms, at least one hydroxyl group, and at least one free-radically polymerizable C.dbd.C double bond, alkyl esters of monoolefinically unsaturated monocarboxylic acids or dialkyl esters of olefinically unsaturated dicarboxylic acids or mixtures thereof, and (per)fluoroalkyl esters of said carboxylic acids, and powder coating materials which comprise these additives for the purpose of improving the flow properties and the surface.