The present invention relates to a mixture encompassing at least one plastic A, in particular polyvinyl chloride (PVC), polyvinyl butyral (PVB), or a polysulfide, and at least one polyester B which can be prepared from a dicarboxylic acid I, and from at least one diol II selected from the group consisting of 1,2-propanediol, 1,3-butanediol, and 1,4-butanediol, and from a monocarboxylic acid III, in particular acetic acid, and also to the use of the mixtures of the invention in casings for electrical devices, in kitchen machines, in computer cases, in piping, chemical apparatus, cables, wire sheathing, window profiles, in interior fittings, in vehicle construction and furniture construction, in floorcoverings, for producing medical items, packaging for food or drink, gaskets, sealing compounds, including those for sealed glazing, films, including roofing films, composite films, phonographic disks, synthetic leather, toys, packaging containers, adhesive tape films, clothing, or coatings, or as fibers for fabrics, or as films for laminated safety glass.