The invention relates to compositions containing water-soluble poly(oxazoline) and organic polymer particles chosen from the group of polyolefins, polyvinyl aromatics, polyvinyl esters, polyesters, polyamides, polyimides, polycarboxylic acids, polycarboxilic acid esters, polycarboxylic acid amides, polynitriles, polysulfonic acids, polyketones, polysulfones, polymeric polyols, polyurethanes, proteins, polymeric carbohydrates, nucleic acids or from a mixture of two or more of these polymers. The water-soluble poly(oxazolin) acts as a stabilizer for the polymer particles and can particularly advantageously be used as a stabilizer in the freeze-drying of aqueous polymer dispersions.
