Abstract: A process for preparing improved molding materials of expandable styrene polymers by coating the particles with glycerin esters of long-chain fatty acids. The coating comprises organosols of pulverulent glycerin esters having 14 to 24 carbon atoms in aliphatic hydrocarbons having 3 to 8 carbon atoms. The proportion of glycerin monoester is at most 40, but not less than 10% by weight and the particle size of the pulverulent ester is less than 100 microns. The molding materials are used to manufacture molded articles.

Abstract: Fine particulate expandable styrene polymers have coatings applied thereto by:(a) introducing the fine particulate expandable styrene polymers into a closed mixing vessel;(b) reducing the pressure in the mixing vessel below atmospheric;(c) preparing dispersions of the coating materials and heating the dispersions to about 30.degree. to 90.degree. C.; and(d) aspirating the heated dispersions of the coating materials into the mixing vessel while simultaneously mixing the dispersions with the particulate styrene polymers to form a coating thereon and drying the coated particles.